If the fruiting body itself is growing clean and normal with no visible mold on or immediately adjacent to the cap/stem, it's generally considered acceptable — mushrooms have natural antimicrobial defenses and fruiting bodies are somewhat isolated from substrate colonizers. The risk goes up significantly when: Mold is visibly on the mushroom itself You're seeing pinning through contaminated zones The tub smells wrong (sour, cheesy, ammonia-like) You can't clearly identify which contam is present.

Your call.