Sexing zombie chicks?

[Thtsalotofchickens]

I just bought some zombie chicks locally straight run. Neither of them have black beaks, but ones is Grey, darker near it's head, and one is yellow. Opposite for their feet coloring. Everything I've read says yellow beak/yellow feet means male. But these dont seem to follow that pattern. Can someone with way more knowledge than me tell me what they think ? Not 100% clear on the lineage and purity of the aysmani roo.
I labeled each chick so it's easier to follow on their coloring

 

[Skyeknight]

As far as I understand the genetics behind fibro sexlinks can only be produced if the father was a fibro bird and the mother dominant white. You mentioned the father was an Ayam Cemani, there is the possibility like you mentioned that the father may not be pure for fibro. In that case chicks aren't sexlinked either. But if the father is homozygous for fibro then these look like all roosters to me

 

[Thtsalotofchickens]

As far as I understand the genetics behind fibro sexlinks can only be produced if the father was a fibro bird and the mother dominant white. You mentioned the father was an Ayam Cemani, there is the possibility like you mentioned that the father may not be pure for fibro. In that case chicks aren't sexlinked either. But if the father is homozygous for fibro then these look like all roosters to me

Yeah im not entirely sure what the bloodline for the rooster looks like. And im not even sure what the mother was for a white hen. My friend bought two from the same lady hatched at the same time and neither of hers have black beaks either. There was only 8 hatched so seems unlikely (I guess not impossible) for half of them to be roosters. Fingers crossed ones a hen

 

[Skyeknight]

Yeah im not entirely sure what the bloodline for the rooster looks like. And im not even sure what the mother was for a white hen. My friend bought two from the same lady hatched at the same time and neither of hers have black beaks either. There was only 8 hatched so seems unlikely (I guess not impossible) for half of them to be roosters. Fingers crossed ones a hen

The white hen shouldn't matter, dominant white is dominant white no matter the breed. Fibro is the same, a Svarthona works just as good. It's not at all unlikely for half to be roosters. A baby is either a boy or a girl so 50% chance of one or the other. So the fact that 50% of chicks are males is a normal sex ratio.