I kind of lean towards all 3. He is proud of the Maggot son, now brother, but he also I think, has to know Josy is into him, and I think he also knows that the MC if a DIK at all is getting pussy at a prodigious rate. Probably John Boy is the only one who gets as much, and it is all with his girl. I think the older DIKs are genuinely in AWE of the performance of the Maggot Brothers, and they will go in the history of the Frat as the greatest pair, to accomplish the unbelievable. I think as one of the founders, Tommy is probably feeling that the flame is going to pass him by, and he will not be the mover and shaker he used to be....
But he has to be proud of what his boy is doing, well except to Josy's tiny sweet pussy, that he probably wants to bang but has some kind of morals and restrictions since it is semi close to incest and not a DPC thing, but he could still be jealous of that.
Of Quinn, I am pretty damned sure nailing her on the rooftop was an epic moment, and one he is pissed about.
Manwhore may not end up with any girls at the end, but it sure is the most enjoyable ride on the journey.