Just finished reading through the whole thing the last few days. Impressive attitude.
I’m not a fiberglass repair expert, and certainly not a pool fiberglass repair expert but I know a guy in New Jersey that does large boat repairs and his pictures sometimes look very similar to your issues. If there’s a lake or river in the area with boat dock or storage you might try asking around for one of those guys that does boat repair to take a look. I’ve also done some much smaller repair work with fiberglass structures so I at least have a general idea of what they’re up against. After fixing whatever caused the crack, they typically grind it all the way down at the cracked area and feather it out a good distance on each side. Then lay in progressive layers of matte and resin. I’m not sure if they would use fiberglass chop on something that small. I’m sure having thousands of gallons of water on it complicates the process and I’m oversimplifying it.
Another problem you have is that any pool repair contractor knows he has to warranty the repair for some amount of time. If the cause of the cracks isn’t resolved, they may not want to repair it just because of the potential for warranty repairs later and lawsuits if it cracks again.
If I wanted to save the pool, I think I’d start by checking for settling of the concrete near the cracks maybe just with a contractors level to see if you can track what happened to cause the crack. Once I had a good guess of its cause, I’d remove the concrete decking at the area near the cracks and try to confirm my theory and take a closer look at the back side of the pool wall. Finding someone to break up and haul off a bit of concrete shouldn't be too difficult and would give any pool repair contractor a bit of peace of mind that the issue is fixable and be more comfortable making a repair. If the pool structure really does turn out to be “done”, the concrete decking you removed wouldn’t have been a waste of money/effort either way.
Hope that’s of some use, interested to see what happens next.