Egads, you didn't need our collective input on this, you play the same parts as the guitarist a lot and he is tuned to drop C so you do the same. Understandable. Your situation is probably a 1%er, so the rest of us were not getting it. A lot of people may not get that(it took about 20 hours for that to come out HERE(, so maybe they tried pressing a 5 on you because they thought
you weren't getting it.

Anyway...
Idea: If you got a double course 4(8 strings) and tuned to drop C, you could get rid of one of the guitarists. Have it wired to send the neck pickup to a bass amp, bridge pickup to a guitar amp, throw some effects on the bridge output.....(joke)