I tend to agree, TB. Magliocco probably lacked the balls at that point in his life, and as you infer, Bonanno was just too full of himself to form a true alliance with anyone.

The Genovese Family, who were in a state of flux at the time (with Frank Costello having already been put out to pasture, and Vito Genovese already jailed for the remainder of his life), may have been the "wild card" in the whole thing, had it come to that.