50% hets mean that there is only a 50/50 chance of the boa being het albino. That means that it could easily be straight hypo. If it isn't albino you wouldn't get any sunglows out of the first breeding, but by breeding with an albino all the babies would be het albino. If the Hypo poss. het albino does prove out I am not exactly sure what your chance of getting sunglows would be.