If asked, Potts is positively in, according to this Assignment X interview. Melnitz in the (fire)house!
AX: Have you heard anything about the rumored GHOSTBUSTERS III film?
POTTS: I don’t have a contract, but I hear it’s going to happen.
AX: Would you be looking forward to reprising your role as Janine?
POTTS: Oh, of course!
AX: Might she be a little more assertive this time around?
POTTS: I have a feeling she might be. I’ll be interested to see what they’ve written.
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