Rusty didn't want the heat. He claimed health reasons but I always felt like he just wanted to use Little Carmine as a puppet and lighting rod to keep the heat off an old man but his plan was to always run the show, just not over assert himself towards the higher ups such as Tony does. Carmine would have done whatever Rusty advised clearly, so you figure Rusty is then at every meeting, gets told everything as not everyone can access Little Carmine if he's boss directly. But who knows, he also had enemies, John or Phil probably would have killed him later on regardless. Food for thought.

Also, the doctor I think would be considered a legitimate associate of the family therefore not the be stolen from in such a capacity without at least a discussion even by a made man like Feech. The doctor fronted for Tony in the HUD deals, he's dumps cash in the executive game, he's their on-call gunshot doctor, such as when Furio takes one to the leg. "I'm a prick doctor, get it?". So I can understand why Tony was pissed at Feech for doing this, if you take into account Feech was fresh out, on probation, and at the time trying to usurp power from anyone he could, making up for what he felt he deserved.