On the surface genetics is simple - but it's never as easy as it should be.
D genes control the 'base' color of an axie, D/- = dark, d/d = white
A genes control albinism, A/- = non albino, a/a = albino
M genes control iridophores, M/- = iridophores, m/m = no iridophores (melanoid)
AX genes control xanthaphores (yellow spots) AX/- = yellow, ax/ax = no yellow
So an axanthic albino may have iridophores if it is ax/ax and M/m
I believe the article you refer to is explaining the axie in th photo, not all axanthic albinos (but I may be wrong). An axie would have to be d/d m/m a/a and ax/ax in order to be albino, melanoid, white and axanthic.
You baby really isn't big enough to make an accurate determination of phenotype yet, you'll have to wait a little longer. My wildtype babies didn't appear to develop iridophores until they were several weeks old, and my albino babies didn't develop a gold colour until they even older.
If you know what the parents are it may help determine the genetics of the babies.