I have two friends who couldn't air refuel to save their lives. Never busted a check ride but they couldn't upgrade either, languishing in copilot hell.

One is at a major now and loving life. Not much air refueling in fifi or guppy.

Keep pressing on, you can make it if your record isn't spotted with failures. If you did bust evals, then hope you can get a regional gig (I'm not sure how they look at busts, I've gotta think they are slightly more accepting than the majors). And if you do, be happy with a regional gig, get that 121 experience and pass all of those evals and then see what happens when the world runs out of pilots in 4 years.

Just my thoughts. Take it for what it is worth.