Larva need proteins to grow so you have to give your queen some proteins. Giving her a fly or some egg would solve the problem I think.
Also, you have to know that Camponotus sp is a genus whose brood grows very slowly (more than a month). So maybe are you a bit impatient ?
I can't speak for apen, but I have kept hundreds of Camponotus before, and I can say with certainty that the brood in the colonies I'm talking about here are not growing, and all my queens are fed plenty protein.
That might be a different issue there. If the eggs are not developing, then your "queen" is likely infertile.
She was a queen I had before and after I moved her in soil she came out fertile and got
workers.
Then what's probably happening is she's eating her eggs and laying new ones. I have seen this happen plenty times making it look like her eggs are not fertile.