User blog comment:AYET/The Dressrosa arc traitor/@comment-4374114-20130910144034

Well let's see here.... if Momo is the mole then why are they fighting on the Sunny to get him from the SHs. If Kinemon is a mole he could have sabotaged the PH arc instead of letting it get this far. Violet has already betrayed DD, and since she isn't around any of the SHs, she went another way, she has nothing to be a traitor for. Rebecca had her chance at Luffy in the gladiator hall but didn't want to take it. TSOR could have been but then what would DD gain from TSOR hiding out Rebecca, unless she has something DD needs, which would contradict making her fight to the death. We have no idea where Bellamy will land or Barty, but neither has really shown they were to help the SHs either.

The remaining outliers are the dwarves or the marines. A dwarf could have spilled about the attack for their own personal gain but so far they seem to be a close group that you wouldn't expect to betray each other. For marines it could be that Fujitora is a traitor but it wouldn't be against the SHs, it would be against the WG.