Orange Room Supporter
The Druz and all Mowahedin in the Mohamadean sectarian practices were Jews who believed that Mohamed was a prophet and they also did not have to convert into any thing new by accepting the prophecy is not an opinion. It is documented in historiography. Mohamed did not bring a religion called Islam. Islam was written in Khorasan.
Only when Zoroastrian converts into Islam invented the Shafeii sect in Nishapur in Iran which was countered by the Muslim Orthodox who were Christian Orthodox converts in Constantinople, that Jews who accepted the prophecy of Mohamed were persecuted and went underground.
All so called Shi'a sects today were sects developed by Jewish converts except the Twelver Shi'a of Iran. They were Zoroastrian converts like the Shafeii.
Druze actually deny Mohammad and call him names. But I'm not sure about proto-Druze, and I believe there's a truth to the Jewish origin of Druze and your theory.