'Til Death Do Us Part: Part 1 - S2-E1
Plot hole: The establishing shot of the White House indicates that President Kelly's press conference is taking place there. A member of the Friends of Humanity disguised as a mutant busts into the room and starts terrorizing the reporters and destroying everything. The Secret Service would have either detained or shot this man long before he could have even gotten close to the press conference. Graydon Creed also shoves a security guard that tries to intervene but somehow isn't arrested for it. (00:05:50 - 00:06:35)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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