My breeding pairs of any cichlids usulally bite the heck out of anything which came near the nest.
Any pics of fish when spawning, or before and after. I never had a mated any cichlids, including rare dwarf specimen which continuously ate their clutch.
Out off curiosity what is pH of your tank water?
Texas Cichlid is very tough cookies and should be able to tolerate/breeding in wide range of pH. If memory serves, male texan bred with very closely related female carpintis resulting in various colorsw and patterns. This of course was in 70's.
I cant forget my first brood of Geophagus steindacneri which I obtained as common fish (70's) only to find out how beautiful fish they were. I am sure they still are gorgeous.
Dont give up yet. How about slight reaquascaping giving them more secluded area where they feel more comfortable.
I know we all want to see what's going on in the tank but how about giving them some privacy until they are more mature/relaxed/experienced with brroding/raising their young.
Good Luck!