I can't remember where but I think I read something that it is possible to bypass this secret with some unique damage types that don't trigger it.
Stuff that comes to mind is:
- Leper gnome deathrattle
- Nightblade's "hero damage" battlecry
- Non spell aoe like baron geddon or abomination
Not sure if any of these work. Is there some way around it? (other than flare)