do fitgirl or dodi repacks install and work on linux?

Yes, proton-cachyos (from lutris or protonplus) can run the installer and the game.

yeah i used to use wine to unpack fitgirl switch roms

Yup, for Fitgirl releases make sure to use Proton 9 during installation; Proton 10 causes the installer to hang.

proton and wine run pretty much everything out of the box. It takes a little bit of figuring out how to run them. If you want to make it seamless and hate the command line, then it's potentially somewhat more work.