So you still censor users payments, even that you give a technical explanation, censoring is censoring. Censoring is not a solution for a non-custodial wallet. It stop being a non-custodial. Instead of talking with Zeus and get to a temporary agreement so they can stop that Zeus Pay system until you find a better solution.

A common announcement to all users (Zeus and Mutiny) it would be much better than just attacking Zeus and their users and tell them to "change LN backend to LDK" because Mutiny can't pay to their Zeus Pay. This is bullying and not fair at all.