Eh... well, technically, if going by what was written in the post and yoshua's description of the spell as well as the general nature of mind-affecting magic, Morgan would [I]not[/I] have been able to identify the effect of the magic on him, and as such the statement "with the magic now gone" would be false, which would consequently induce the discomfort yoshua described when acting despite of it.
Basically, submitting to part survival instinct and part vengeful anger is not the way to cancel the spell, only to defy it... if that makes sense. It wouldn't allow him to break the magic affecting him, but it would give him the determination to push through.