Off center will not matter. Unequal rod lengths will be a disaster. I agree completely that you should not use a wheel collar for a joiner. Try drilling a hole on opposite sides of the rod (dowel?), one of them 1/4" or so farther up the rod than the other. Make a "L" bend in the rod to slip into the holes. You can file a small groove on both sides of the rod for your wires to rest in. Temporarily hold them in place with CA and then wrap the entire section from the holes to the end of the wood dowel with a heavy thread and saturate the thread with thin CA after wrapping.

OR, you could just use a piece of heat shrink tubing over the wires to hold them in place. Whichever you think will suit you needs best.