I like your theory but it has holes.
These two witnesses are walking up and down in the temple in Jerusalem while the world is outside the temple (this is mentioned when John is told to measure the temple).
The two are killed and left lying in plain view.
I believe that these two may represent the two lampstands/congregations. That is feasible. But unless we have a mass killing of Messianic Jews and Christian Gentiles, that doesn't make sense.