I think between Joe and Luiz you guys pretty much nailed it. The fish surely has the markings of Rhinecanthus rectangulus, the eye bands, head, and yellow face strip of Rhinecanthus aculeatus so it appears to be a hybrid between these two.
Joe does bring up a very valid point that although R. aculeatus has a thin brown band between the first two white stripes running from the anal fin towards the eye, it does appear to have similar characteristics/markings of the super rare R. cinereus.
Could this fish simply be a hybrid between R. rectangulus x R. aculeatus, or is it a multispecies hybrid?
Very unique fish indeed.
Luiz and Joe, I think both of you guys are up.