Yes next time I would suggest a pot so they can lay them better in there.
Also yes they're a breeding pair and they change morph colors as they breed. My female was like yours dark and vibrant. My male as well and after the male his green and blue popped like crazy.
The dark one is the female. Because FHs are a combination of trimacs hybrid with something else, these 2 are displaying a trimac breeding pattern.
They could be pure trimics, but that's suspect these days, with all the random mutting. In any hybrid cichlid, there are a percentage in a spawn, that will favor one species of parent or the other. In this case the trimac gene seems dominant in these individuals.
Here are a couple pure trimacs in breeding dress to illustrate, very similar.