I never understood how the bedroom assassins died in part 2 ?
I suppose Fredo could have killed them.
To me Tom Hagan always seemed abit shady in the following scene when Michael tells him it wasn't a lack of trust or confidence.
Was it ever explained who killed them ?
Could this be just one of those situations, shall we say "plot hole" When Hitchcock was faced with a question he couldn't answer, he is known to say "Its only a movie".