"When a Pokémon with this Ability is hit by a move that makes contact, there is now a 30% chance that the attacking Pokémon will become poisoned, paralyzed or asleep: there is a 9% chance of poison, 10% chance of paralysis, and 11% chance of sleep."

This is a direct quote from the Bulbapedia page for Effect Spore.

My question is, would a steel type like Corviknight still have a 30% chance to activate effect spore? And if so, would the poison chance still occur 9% of the time without working? Or would effect spore's odds change and have something like a 15% chance to paralyze and a 15% chance to sleep? Do we know the odds for this?

And my secondary question, for combo types, like magneton or toxtricity, would they then have a 30% chance to get slept?