think what's annoying about this is not as much Maya doesn't appear
but that Eshiro was cheap enough to keep saying in every interview 'You have to play and find out' instead of saying no or no comment. We all know what WAS shown doesn't count and Eshiro does too.
Also I'm betting no actual plot is going to be given for why Pearl can just visit but Maya can only send letters or something. Why couldn't they just have explicitly written Maya was on some world spirit channeling tour right now or something? It's better than just deciding she isn't there for no given reason.