I have tetras, WCMM, guppies, rams and cory cats none have touched it. The only ones to go near it are my gouramis and they jusy strip the hair algae off it.
The mollies might not eat any, but the brackish conditions you should be keeping the mollies in might. Besides, java moss appears to be immune to even a clown loach's feeding habits, so it's probably fine.
BB's will bite and nip it. But it should live threw it. They tend to bite and nip at most soft leaf plants but they take very small bites mostly wanting the algae that grows on the edges.