well since the posi wire goes to the motor and the battery that one is ok. now the blue motor neg. wire and the black battery neg. wires are different at least the are both neg. feeds. so it may be ok. did it work as normal wired up the way you had it? or did it not feel as responsive in either acceleration or in braking operations, or did you not even notice a difference? its not like you sent voltage into the esc from the posi side into the neg. you'll just have to do like you said and rewire it and try it out.