I would just them play it out.
If you have a fish that you think won't eat fry then he may 'bond' the pair better.
Most pairs do better when defending as opposed to just being mad at each other...
But most fish that can will make a meal of fry so
IMO you are just best to let them be.
I am waiting for my wild kribs to spawn in their 29 g..Once they have a spawn or two under their belt I will work them in a separate tank if I have not[or they have not] had success in the set up they are in.I think they may just do fine without much help from me...
ATM they share the 29g with orange laser cories {may really be trouble?} and 2 otos...
Possibly adding extra small structures the parents can not get in but fry can will help in moments of panic for the fry? I know for many fish I breed and leave with partents I use broken terra cotta pots scattered on bottom of tank to offer shelter for fry that parents can not get them in...