Very poorly justified by the fact that Mary Jane did not notice the change, that is, when the chameleon Replaced Peter on one occasion by a touch, she knew it was not him (before OMD).
The second time he did it alone compartiron a dinner, but here it's been weeks and not think it's weird?
I can almost bet that Cardiac will die, what with Slott loves to kill their characters. Like seriously weird being expelled without researching first, otherwise the story would not be realistic.