I've been cave diving for 15 years and am a local. I've instabuddied enough times including those recommended by friends or respected instructors and have had enough bad experiences to not enjoy finding new buddies. I still will, but it is always 100% assuming I'll be solo diving with someone in my same vicinity. I know I can help them, but I'm often not convinced they could help me. My wife last year or so dove with a new buddy recommended by an instructor we respect and she got stuck in zero vis because the guy couldn't handle buoyancy in any passage not big enough to drive a truck through.Or call the dive and try again with someone new the next day
I've done a decent amount of cave dives with instabuddies I got from an instructor's contact list and haven't had a dud yet
Not saying its not going to happen but I'd be willing to bet the number of qualified/good people on your instructors previous students list is way more than people who suck
Once you find more people who are good on their skills you can branch out from there with people that they dive with
heck you might even make a friend in the process!
The benefit of diving with GUE divers is most of the time you're diving with like-minded people who dive with a high level of skill. But there are some GUE divers I will not dive with either due to skills that need to sharpened or unsafe attitudes. It happens with people certified by any agency.