Does anyone with Healthcare background know if my fiancé should go to the ER? He ate part of a cuban sandwich and discovered it had maggots in it... HELP

He has digested them, thankfully, probably sooner than the meat in the sandwich.
Stomach acid is magical stuff, as potent as any acid can be.
The stomach wall is even more magical.
People in other cultures eat maggots for protein.

If he still is wondering, go look at some old episodes of Fear Factor, the reality 'gross me out' show, where part of the show involved eating all sorts of disgusting things.

Free protein, nothing wrong with them at all