there would certainly be no problem with using your assets from the e1m1 RGM game, but there will be a theme announced this time around that's gonna be mandatory.
it's gonna be a flexible theme, so i don't think it will be a problem for you to modify the terminus assets to fit the theme. but when you publish, publish it as a separate game, not an updated download on the e1m1 jam game you made b4.
make sense?
and you get 2 months this time, so there will hopefully be plenty of time for ppl to make assets.