Hey dentillozie,
‘score’ the top of the dome several times with a scalper or razor blade, be very very careful to not hit the yellow phosphor though.
I have found 2 things out by doing this.
1) It quickens the dedome.
2) I think the petrol penetrates right through the dome, which does indeed fall off (or crumble away) and gives a nice clean dedome. In my (limited) experience, the methylated spirit ‘bath’ in a 35mm film canister, swirled around so the spirits agigitate over the emitter, has every time left a clean dedome. No need to try and scrape any dome off, which as you’ve experienced, will destroy the gold contact wires!
Hope this helps somewhat.
Rob