I'm on PC and well into my second playthrough. The first time, I didn't encounter this bug at all. I wondered if rescuing Florrick too early might be the problem, but then Matchine mentioned the alternative NPC. To my understanding, that person accosts the party if Florrick has been executed. I busted her out of jail right after Gortash's "coronation". The first time, I didn't save her until later in Act 3. For science, I will continue my playthrough to see if Mizora actually holds up her end of the bargain, and report back.
I have a save file named "Florrick Bug" that starts just before she spawns in outside Sorcerous Sundries. I hope it might provide the devs some insight into what went wrong.
Full disclosure: I broke the pact, and then reloaded an earlier save because it didn't feel right for my Tav.
