Looks more like a ZZ to me. But who told you it is a Malau? If someone told you its a Malau, it can be possible that it is a Malau. Fish may change a whole lot in the future...
Not a good quality but give him some time. As they get bigger he may be. Pump him up, lots of water changes, good variety and good quality food, he will look nice. He's kind of skinny, needs some food.