Interesting observation.
Milingu suggested that he might be "juiced" I am not sure what that means, but maybe that could account for the yellow/blue look?
When he is swimming (and not flaring his dorsal fin), he looks a lot like a yellow tail acei?
Only one catch locations has red fins in the females. That's why it's also called Kandango red fin. Most of the over 40 other locations show silver or yellow fins. But as I said it's too yellow for that. Sometimes juiced = hormone treated females show way more colours than naturally possible.
Could also be a hybrid or something totally different.
Like with the most Malawi cichlids in trade that come without clear species you can only speculate.