I'm a bit late replying, but thanks for the guidance, Goober. Work was pretty intense this week, and I barely booted my PC up at all until today. Unfortunately, I still could not figure out how to "install" wxLauncher in Linux, but I think this is down to me just being pig ignorant regarding this OS and the way things are done in it. I've seen that someone has made a tutorial for CMAKE somewhere on the forum. Assuming I survive to Christmas vacation, I'll spend some more time teaching myself how to do this the right way rather than just mooching off repositories.
Which is what I finally did and was able to get to work. Somewhat. The wxLauncher deb I found has a somewhat strange version number "0.11.0+dfsg-1" And for reasons I cannot figure out, the FSO ... what do you call them in Linux? Are they still considered "binaries" or "executables?" I don't even know the right lingo for this thing. Anyway, for reasons I can't figure out, the FSO Linux executables downloaded by the FreeSpaceOpenInstaller did not work. Wouldn't recognize my joystick. Wouldn't show anything under the "advanced" tab in wxLauncher (no flag options). But when I copied the ones Knossos downloaded over, they worked just fine in wxLauncher! So I'm a lot better off than I was before. Still pretty clueless, but I've got something that works! So, thanks to Goober, tomimaki, Chief1983, and everyone else who helped out over the several threads I posted to.
Hopefully, eventually whatever is wrong with Knossos and Linux Mint gets figured out. That thing just makes it all so easy I honestly didn't even think that much about how much it was doing in the background.