They can't touch him because maybe he is still enjoying the dream.
I am guessing even though it is their illusion, him being a demi-god now can claim such vision as his 'domain' and no one else can even bring their magic into it.
man this is such a huge emotional hit for Raoul. It's a shame what he about to do to the ones who made this illusion magic... well not really they deserve everything that's about to rain down upon their shitty lives