If this were me, and it was a crank I absolutely wanted to save, I'd take a socket that has the same diameter as the pin holes, then I'd grind the socket away until 2 "pins" were left. I'd put the socket on an impact wrench and, with the bike BB sitting against something solid, lean on the impact wrench and remove the rings.

Luckily, you have two chances at removing this crank. First I'd try an impact with a 6mm allen. If that strips, usually allen socket cap screws strip in one direction, you you should be able to tighten the allen again (taking the pressure off of the extractor ring.) Then I'd make the socket thing I mentioned above and try again. Once you get the extractor ring out the allen should come out easily since you already loosened it.

If all else fails, hammer a torx bit into the allen and use an impact with that. If that fails, hit the extractor ring till it breaks. (Alternatively, cut it off with a dremel.)

Those bolt "removal" tools aren't meant to remove a STUCK bolt, they're meant to remove a looseish STRIPPED bolt.