(Samuel said)
I would say to comment out all the lines from 91-98.
Done. Re-booted. No more error messages before the grub menu appears.
Thank-you!
Now to the greater problem...
When I upgraded to Fedora-28, the text of the grub menu was
significantly down-sized. It also seems to be a (darker?) gray. It is
split into two pieces into the corners of the left side of the left
monitor. It is difficult for me to read. How do I make the font bigger
and whiter, and get it all back together?