I think it wouldnt go that well even if Failin, Shuro and Marcille saved Laios had he been the one eaten by the dragon. They wouldnt think about eating monsters and they wouldnt form bonds with their cook because of that missing concept. They'd struggle on rations and even if they did manage to beat the mad sorcerer.. they wouldnt think of eating the demon.. they'd probably be consumed by being the next lord of the dungeon ┑( ̄Д  ̄)┍
Laios was.. an extremely.. insanely odd case. His thought process was so different that it helped them beat a demon and avoid the bad end. The story was so exhilirating and there were some dark parts but them being goofy and idiots in most parts totally balanced that. ヾ(❀╹◡╹)ノ~
I really doubt Marcille would let Falin go in again by herself, that “what if” was totally based on Laios perception and not reality (though Madcille would 100% ditch him if Falin wasn’t involved lmao)