Congratulation with the spawning.
The male is taking the eggs in the mouth as he attempts to get these to sit in the nest. They probably fell down – where they are now lying on the bottom of the cave – and he is trying to get them to stick in the nest. Parosphromenus are in no way mouthbrooders 😉
That the eggs doesn’t stick to the ceiling of the cave has to do with the water and microsiemens not being low enough, – what is your water quality in that regard ?
It seems your paros are willing to spawn – but being together with chocolate gouramies there will not be any offspring growing up.
It doesnt matter whether the cave is at the bottom or floating, – paros often choose caves situated at the bottom as well.