Okay, I think I solved it. Not in a way I would have liked to, but it did solve it.
Simply put, I was no stranger to different rom sets that included "scene/group" releases, and of course those frustrating start-up screens, which at best usually just break functionality with cheat codes. But the last straw was when I had loaded up a GBA romset on my EZ4 and had about twenty consecutive games I wanted to play having those rips and then the splash screen basically breaking the ROM's ability to run. So, in spite of how Nintendo wanted to make this difficult with litigating a bunch of the more accessible sites, I resolved to try and stick with
NoIntro Rom sets, that are just the pure data.
this was no problem with everything,
except the NES games, because after asking on a discord specific to these units, one of their admins found the romset's data has no header data at all. Not a bad thing, but the only emulator available at this time that
can open headerless NES games, is painfully slow.
my solution, in that sense, was to find another rom set to download (since I didn't have the original set on disk) and add in those via Hakchi. Those all work, now. And after some tracing back and forth, now all the games work. And I can now pack the bugger up and send it back to my co-worker buddy.