After about a day working on this problem it appears that the installation of Gnome destroyed my boot files for Plasma. As per the advice of Julien I installed rEFInd onto a USB stick and booted from that. It showed that I had two versions of Solus. But when I tried to boot into the Plasma version my machine kept crashing with an error about missing files. At that point I could still boot into Gnome from the USB stick using rEFInd.
I then installed rEFInd onto my system and after that I couldn't boot into anything. Not Gnome or Plasma.
So I then used Ventoy and installed Budgie in place of Gnome. After that install and update I was able to get to my files from the Plasma side and copy them over to the Budgie side so I didn't lose them. I suppose my next move will be to replace the Plasma side with something as it will not boot. And I haven't found any way to repair the damaged boot files.
As a side comment after I installed Budgie I installed Opera browser and it is working great. Under Gnome it was very sluggish and crashed twice. It seems Gnome is just not for me. Glad Solus has other options because I really like Solus.
I suppose this could be marked solved. But I don't know why Gnome trashed my Plasma install.