Did not even think to check for the pharyngeal molars, Eric, but will next time.
GRES is a GSF/RES hybrid. No telling how many backcrosses happened to render these specific fish, but you can see different characteristics in each although I strongly suspect these are some generation of GRES.
Scott you should recognize one of these fish - I strongly suspect we sampled it in the fyke net this Spring! Remember the split caudal fin?