“executing grub2-install install failed /dev/sda *reloaded

I am trying to install Ubuntu 20.10 using a custom partition setup on my /dev/sda device. I can install Ubuntu fine using the defaults, but I do not want defaults. I want a larger /boot sector.
Upon creating a custom /dev/sda1, /dev/sda2, /dev/sda3 and /dev/sda4

I am getting the exact same error as this guy

same error

But none of the solutions work. There is no

automatically install to MBR of first hard drive

Option.

Dell Inspiron 7359

UPDATE:

device directory during a typical boot

rad@rad-laptop2:~$ ls /dev/
acpi_thermal_rel          iio:device3   sda3      tty28  tty63      uinput
autofs                    iio:device4   sda4      tty29  tty7       urandom
block                     iio:device5   sdb       tty3   tty8       usb
bsg                       initctl       sdb1      tty30  tty9       userio
btrfs-control             input         sdb2      tty31  ttyprintk  v4l
bus                       kmsg          sdb3      tty32  ttyS0      vcs
char                      kvm           sdb4      tty33  ttyS1      vcs1
console                   lightnvm      sg0       tty34  ttyS10     vcs2
core                      log           sg1       tty35  ttyS11     vcs3
cpu                       loop0         shm       tty36  ttyS12     vcs4
cpu_dma_latency           loop1         snapshot  tty37  ttyS13     vcs5
cuse                      loop2         snd       tty38  ttyS14     vcs6
disk                      loop3         stderr    tty39  ttyS15     vcsa
dma_heap                  loop4         stdin     tty4   ttyS16     vcsa1
dri                       loop5         stdout    tty40  ttyS17     vcsa2
drm_dp_aux0               loop6         tpm0      tty41  ttyS18     vcsa3
ecryptfs                  loop7         tpmrm0    tty42  ttyS19     vcsa4
fb0                       loop-control  tty       tty43  ttyS2      vcsa5
fd                        mapper        tty0      tty44  ttyS20     vcsa6
full                      mcelog        tty1      tty45  ttyS21     vcsu
fuse                      media0        tty10     tty46  ttyS22     vcsu1
gpiochip0                 mei0          tty11     tty47  ttyS23     vcsu2
hidraw0                   mem           tty12     tty48  ttyS24     vcsu3
hidraw1                   mqueue        tty13     tty49  ttyS25     vcsu4
hidraw2                   net           tty14     tty5   ttyS26     vcsu5
HID-SENSOR-2000e1.2.auto  null          tty15     tty50  ttyS27     vcsu6
hpet                      nvram         tty16     tty51  ttyS28     vfio
hugepages                 port          tty17     tty52  ttyS29     vga_arbiter
hwrng                     ppp           tty18     tty53  ttyS3      vhci
i2c-0                     psaux         tty19     tty54  ttyS30     vhost-net
i2c-1                     ptmx          tty2      tty55  ttyS31     vhost-vsock
i2c-2                     pts           tty20     tty56  ttyS4      video0
i2c-3                     random        tty21     tty57  ttyS5      video1
i2c-4                     rfkill        tty22     tty58  ttyS6      wmi
i2c-5                     rtc           tty23     tty59  ttyS7      zero
i2c-6                     rtc0          tty24     tty6   ttyS8      zfs
iio:device0               sda           tty25     tty60  ttyS9
iio:device1               sda1          tty26     tty61  udmabuf
iio:device2               sda2          tty27     tty62  uhid

mount points on device during regular boot:

rad@rad-laptop2:~$ mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=3921712k,nr_inodes=980428,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=793804k,mode=755)
/dev/sda4 on / type ext4 (rw,relatime,errors=remount-ro)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,size=4096k,nr_inodes=1024,mode=755)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
none on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=21720)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
/var/lib/snapd/snaps/gnome-3-34-1804_60.snap on /snap/gnome-3-34-1804/60 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gtk-common-themes_1506.snap on /snap/gtk-common-themes/1506 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/core18_1885.snap on /snap/core18/1885 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snapd_9721.snap on /snap/snapd/9721 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snap-store_481.snap on /snap/snap-store/481 type squashfs (ro,nodev,relatime,x-gdu.hide)
/dev/sda2 on /boot type ext4 (rw,relatime)
/dev/sdb2 on /boot/efi type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=793804k,nr_inodes=198451,mode=700,uid=1000,gid=1000)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
/dev/sdb1 on /media/brad/Ubuntu 20.10 amd641 type iso9660 (ro,nosuid,nodev,relatime,nojoliet,check=s,map=n,blocksize=2048,uid=1000,gid=1000,dmode=500,fmode=400,uhelper=udisks2)
/dev/sdb4 on /media/brad/writable1 type ext4 (rw,nosuid,nodev,relatime,uhelper=udisks2)