Well, there may be a fusion of protons in an accretion disk of a small (a few suns) BH if density of falling hydrogen is high enough. But inside BH a fall seems to proceed so fast (by local metric) that the density could probably be even less than outside.

If protons fuse inside BH, their gamma-radiation and neutrinoes do not go far above event horizon (EH) crossing it from inside, (and they may even never reach EH if fusion happens close to singularity). So all energy seems to never get out for infinite observer.