Good looking pair you got there.
Just keep them stable, with little to no temp or pH fluctuations and in the same tank with a divider then wait till the female is ready to go. Sometimes swinging the parameters and raising the salinity messes with the female's egg laying cycle. Do water changes weekly, it helps stimulate them.
Female infertility is actually rare with flowerhorn and other hybrids, even in F1 crosses. Most commonly, infertile females won't lay eggs as opposed to laying bad eggs. So if your female lays eggs and tends to them (some do not making them a bad breeding choice) then there is at least a 90%-95% chance that the eggs and the female are fertile.
You need to give your female time. It takes at least a year and a half to see if she will lay eggs. Remember they are hybrids and sexual maturity is a trait that can be manipulated like any other trait. If she doesn't lay eggs by then, then I would assume that the female was infertile.
Your male is beautiful and looks like a perfect specimen of a jk or fader x zz strain. I highly doubt that he is infertile. Your female looks like a Red Texas cross which would be the reason for her white eyes. Texas cichlids, unless line bred to have red eyes, normally have cream colored or pale orange eyes.
There is a "theory" that suggests that white eyed flowerhorn/kamfa are infertile or have a higher chance of infertility. Sadly, this is not true. Too many times have I bred red eyed males only to discover they were infertile. Also, the "theory" only applies to males, regardless its complete bs. I only bring it up as you mentioned their eye color specifically when describing them. Just want to clear the air on that.
Keep trying and good luck
