Umm fish(andy)- your kidding right?
I ask because both banggais and pyjamas are mouth breeders and it seems to me-improbable. Its one thing to be a haremic spawner, and the pelagic eggs get fertilzed inadvertantly when a number of angels are breeding the same time, like what can happen w/ centropyge angels.
But to have a female banggai be receptive to a male pyjama, or vise versa. The only way possible i can see is if both pyjamas and banggais are spawning in extremely close quarters, and gamates floating into the mouth of a carrying male, and fertilze a unfertilzed eggs.
Lastly, the fact that these fish are closely related but considered different species doesn't help here. Pyjamas are apogons while banggais are pterapogon
Of course in nature anything could happen- I may be totaly wrong
A picture is worth a 1000 words