Ok here are more picturesThe hiding fish looks to be a male going by the body shape and orange chin though he is still young, could you post another pic of him and post pics of the other two as well? if they have paired they are not going to like this juvenile male hanging about.
They are beautiful fish I have only ever had one, a male, for many years now, he is fully grown and so beautiful and no trouble, but never had his own kind with him!
Male:
Bigger female:
Smaller female/ younger pearl gourami: