I got Neo Geo games working now. Only issue is that I have to do it via the Terminal with stuff like:
./mame64 miexchng
I can't launch the executable by itself or it says the ROM has missing files (even though the command line launch works perfectly). I can't get it working via either QMC2 or Erockus despite having the proper directories set in the paths preferences. Only via Terminal.
I can deal with that, it's just super annoying. But it beats nothing at all.