The pics of Edvet don’t show P. sumatranus but a form of the (Sumatranian)-bintan-like variants.
The short (!) filament in the tail of sumatranus must be visible in fish of that size; it’s 1 mm only, but here it’s not to be seen at all.
The rounded spot to be seen in some individuals is not conclusive of sumatranus; it is present in some bintan-variants, too. It is much more distinct and peculiar in sumatranus.
At least the one in the third picture seems to be real sumatranus. You can even see the red band in it’s dorsal fin. They’re from the same batch as mine, which undoubtedly are the real deal.
My sumatranus didn’t have the filament in the beginning, and even now it’s not always clearly visible in all indivuals. Some even seem to lack it completely. Their courtship dance is head up, so they really are sumatranus.
I don’t yet exclude the possibility of them being sumatranus. Wait until they show their true colour.