Never said he cant ignite his body in flames, said he cant ignite his body in flames with sheer will alone, or else he wouldnt be in the situation he is now, would he? That pannel you showed was purely for comedic efect.
If he escapes with fire by himself from the gifters that are holding him, then yeah, you are right....If not, then its proff that he needs to be able to move to ignite himself.
If he escapes with fire by himself from the gifters that are holding him, then yeah, you are right....If not, then its proff that he needs to be able to move to ignite himself.