I had similar bad timing/unsuccessful at snagging a fighter unit spot when I was in my 20s, and I was in much worse econ position than you in that I wasn't making major FO money at such a young age, nor had the flying quals to be one during the lost decade.
I still wouldn't enlist for the sake of a UPT slot, it's a very low percentage play in the aggregate. Odds are you'll end up spinning your wheels and end up encumbered with the impositions of an enlisted job that isn't really going to add much to your primary income generation career.
As to fighter or die thing, I get it, I resembled the remark too. Given my experience with the process, and my own outcomes and history now as a middle aged guy within spitting distance of the jelly of the month, I know what advice I'd give you, if you weren't a major FO already.
..But you are one already. As such, I'd just focus on your airline career and fund the F1-rocket/Gamebird airplane fund if you can't get a fighter spot tbh. But I'm me, I'm not you.
Good luck to ya.