Other mistake: The non-English wording on Cocteau's tombstone at the beginning of the episode is gibberish. It says "Pace et Rfouisat." When it is shown again at the end of the episode, it reads "Page et Resquiat." It appears that they were attempting to say "Rest in Peace," but they got their French and Latin confused. The proper French translation would be "Repose en Paix" and the proper Latin translation would be "Requiescat in Pace." (00:01:35)
Other mistake: When Wolverine and Captain America are scaling the cliff, their bodies glide up the cliff wall between arm and leg movements. (00:07:30)
Other mistake: The Red Skull reveals that Cocteau is the one who sounded the alarm on Wolverine and Captain America, but at the time the alarm starts going off, there are no switches on the walls for him to have pressed, not to mention he was shown to have been standing in the middle of the corridor out of arm's reach of either wall. (00:09:35 - 00:10:20)
Other mistake: When Justine is telling Wolverine about her father's accomplishments in the war, the cel shading is very fuzzy throughout the entire shot. (00:18:30)
Other mistake: When Wolverine is carving "HERO" into Cocteau's tombstone, he is shown to be using all three claws on his right hand to do so, but the carving looks like it was only carved with one sharp point. If he was using all three claws, each point of articulation for each letter should have been tripled. (00:19:05)
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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