I've interpreted that as Josy wanting to come up together with a cover story they could tell Maya, that would hide the fact Josy and MC potentially slept together. She wanted to work out the details so they wouldn't be discovered by their stories mismatching.Josy ask mc "what are WE going to do" clearly she wanted to tell Maya why else would she ask that, it would not make any since what so ever if she didn't.
She was probably planning to tell Maya about that guy she's met, and to tell MC about that girl she's with, but definitely not in the way that occurred and not with all sordid details.