I’m tossing together a simple module and one side has the option to hide units. Giving their side’s main prototype the Invisibility option and restricting it to that side works perfectly, as it should.
But moving a hidden unit toss this into the log:
? moves ? → ? *
when in the game the rules do not require you to disclose whether you’re moving hidden units or not. In fact, they actively encourage you to BS this part of your turn to throw off your opponent.
Is the reporting being generated by the Map itself? You could try replacnign the automated reporting of moves for all pieces, generated by the Map, with customized move reporting from a low-level Prototype which first tests for invisibility.