You said :
"The debate here, for me, is not about whether there is rebirth or is not rebirth, the central point I am working on is whether the Buddha *taught* rebirth as necessary to his path."
You are assuming that there is only one path and that we are all on it. Most lay followers and most monks were on the "wrong eightfold path" which is most certainly not the noble eightfold path.
Some of the Buddha's teachings are ambiguous and are understood in one way by those on the wrong path, and in another way by those on the noble eightfold path.
A belief in rebirth was expected of those on the wrong path. Since they had a "view of self" they would not ask "What is reborn?", for them, it was obvious.
Best wishes, Vincent.