Everyone is a timebomb anyway, that is the message of WoW. Judging by the Visions of N'Zoth, the fruit vendor in Orgrimmar is a timebomb, the drunk grunt in Orgrimmar is a timebomb, even the righteous Thrall is a timebomb. No one can hide from the Void, no one can resist it.
But the Ren'dorei have one advantage that the lesser races don't, and it's their sheer willpower and knowledge, which makes them the hardest mortals to corrupt. Who'd succumb to the Void faster? A random drunkard who doesn't even know what the Void is, or an elite elf who has been training non-stop to resist the whispers?