After Joey returns from the void, he discovers that Gavin is doing something hideous to Rosa. Joey can't do anything to Gavin or stop what he's doing; only Rosa can stop it.
Hint 2
You can't switch back to Rosa right now. The only thing Joey can do is talk to Rosa and somehow convince her fight Gavin's mind control.
Hint 3
Rosa is completely in Gavin's power, like a hypnosis subject in a cheap 1960s sitcom. Being gentle and soothing isn't going to help.
Hint 4
You need the most obnoxious, cage-rattling, offensive remarks you can find -- the verbal equivalent of a slap across the face -- to wake her out of this trance. When you pick the right response, Rosa will turn away from Gavin just a bit.
Hint 5
Remind her of Gavin's four victims that you've met, then pick the nastiest, most personally insulting remarks about each one. Specifically, choose these responses:
Buy me a coffee