As it stands, there's a relative dearth of content for Anna/MC after letting Josef stay without sharing. It would be hot to have the MC still get the bedroom key, and have sex scenes with Anna there. It could even be locked behind a "Man of the House" quest line where the MC really replaces Josef (perhaps with other responsibilities around the house, beyond just providing financially). If the MC begins to help Josef out more directly (e.g., getting him a managerial job somewhere, helping him get another partner [Isabella again? River?], buying nice gifts to show appreciation for his upbringing), it's possible Josef would even be more agreeable of the situation. As it stands, it feels kind of jarring that Josef accepts that his "tenant" and wife are fucking, even if it is to pay off debt. I mean, Josef's a stud himself. There's no real reason Anna doesn't ask him, beyond genuinely being more attracted to the MC than Josef.
Once everyone in the house is aware that Anna/MC are running a Starmaker page (i.e., it's known that Adrian is subscribed to Anna's page, Josef has been told about it), Anna and MC should have reduced concern about being found out. Why not let Josef or Adrian walk in/watch them doing it? They MC/Anna could be observed fucking while camping, at church, at the beach, and different places within the house. Everyone being aware and accepting (without necessarily sharing) adds another level of eroticism, and would really highlight either Anna's corruption, or blind love for the MC (depending on the way it's written).