After my all my "fun" exploration (and thinking about the DSS for thirty years), the answer to my question (as far as the internal data goes) has been right in front of my face this whole time. I don't think the Teacher was Jesus (or James) because the Teacher is said to have been "swallowed" by the Wicked Priest (which I take to mean "destroyed") on Yom Kippur, and Jesus and James are said to have met their ends by a "wicked priest" on or around Passover.
So that's that, as far as I am concerned. Everyone can relax now. But I'm still gung ho for the Fourth Philosophic origin of Christianity and the Teacher, though I couldn't tell you which Fourth Philosopher the Teacher was. As Jesus said, "Many will come in my name and say 'I am He' and deceive many." Otherwise, spin's guess (Onias the Righteous) seems promising, though that is not without some internal data issues too (which I once addressed in another thread long ago and need to revisit).