I wouldn't put that bleach powder anywhere near the bone if I were you.
I've had excellent results with all kinds of skulls (raccoon, coyote, moose) boiling the bone in a solution of part hydrogen peroxide part water. I've always just used 3% peroxide from the grocery store so 40% should do just fine, try 1:2 peroxide to water or 1:1.
1. Put the bone in the solution and then turn the heat up so you don't crack the teeth.
2. Boil for 10-15 minutes, maybe not even that, and then scrub to make sure everything's clean.
A few times I've had to boil, scrub, boil, scrub, but I'm usually getting the meat off at the same time as I whiten.
Good luck!