Alright, let's look at this again, because I think that you talked yourself out of the winning hand here by focusing on possible draws instead of range of hands.
-CHR has been capping everything, and took the lead preflop and on the flop. He is playing like a bully, because he knows that it will get people to question the value of their hands rather than focus on the ranges of hands.
-Gambler wasn't check/calling, as he never used his check option. He was merely calling bets until he raised on the river. He raised the river to play back at CHR so that he could possibly get CHR to flat call rather than cap the pot. Gambler had to make this play to try and take the pot because he was pot committed, and might have gotten CHR off the hand by playing back at him.
-You had multiple opportunities to take control of this hand, and were too passive because you knew that they were going to continue to cap the pot in the event that you raised.
Your mistake in this hand is that you knew CHR was a maniac, and you never played back at him because you were afraid that he would return the favor. The best possible outcome in this hand would have been to bet at CHR and make him defensive. Then Gambler is calling your bets, which he would have done on the river had you made any kind of play on the flop or the turn.
You can eliminate CHR from having either a straight or flush draw because he is simply playing like a maniac, and the maniac is more likely to allow you to control the betting when they are holding the nuts so that they can maximize the value of their hand. Remember, he plays like a maniac to steal bets, but plays smart when holding the nuts so that he can sucker you into taking control of the hand.
I also think that you could eliminate Gambler from being on a draw here due to the fact that he didn't try to take control of the hand until the river. Why do I say this? If he had a straight or a flush draw, he would have clearly raised on the flop to try and eliminate any potential confrontation that would take place on the turn or river if he did not make his hand. He would have at least made a value raise to try and steal the pot theb instead of adding big bets into the pot on the turn and river. I could see a smooth call with a straight or flush on the turn, to provoke CHR into leading out on the river, but given CHR's betting pattern, I think Gambler would have been observant enough to know that CHR was capping every stage of the hand when provided the opportunity, and he would have maximized profit on those hands by making a raise on the turn.
I know it is a lot to consider in a short period of time, but these are the things that I picked up on when I initially reviewed the hand history. Have confidence in your reading abilities, as you were right in this situation and talked your way out of making the right call based on the information that was being given to you by your opponents.
