Johnny Dogs or Gina.
Case for it being Johnny
> Aberama says that only Johnny knew where Aberama and his son were camping. He believes Dogs betrayed him and led those people to them.
> Dogs literally fucking Tommy's maid behind Tommy's back and Tommy saying that only being a mole would get someone fired. Foreshadowing.
> Tommy saying he can only trust Johnny Dogs. Sus.
> At the end and when the plan is failing of all the people in the backstage, Arthur, Aberama and Johnny only Johnny doesn't get attacked by anyone. Throughout the entire season it seems Dogs always misses danger somehow and always somehow knows what to do or say to get Tommy's trust.