Funny thing, at this time I think the power lied with Sonny Reds faction, he basically controlled a third of the family capos, his mistake was thinking that this power enabled him to not pay for Sicilian heroin, which made them betray him.Also,on the hits being Bonnano guys, I think its kinda mob etiquette that if its your problem you should be able to handle it, especially if you want the power.
Think when Gotti hit Paul, in his book Sammy says the hitters were all,from Johns crew cause it was basically his problem.
Or the three capos, it was to protect their heroin pipeline, so they actually brought in a shooter from Canada, as well as using George for the setup, that wasn't really necessary, but it was if they want to hold onto their interest from a position of strength...

They did use em for cleanup though they did a terrible job.(maybe thats why they weren't used, this was a hit that couldn't be fucked up)