OK, Since this engine has the smoke unit mounted in the shell, you could trace the red AC power wire from the spring pad on shell and then just jumper track power with leads to the red wire, and also the shell as chassis ground.
PS-1 smoke units get track power from the engine, not via the tender. The harness sends AC power to the tender for the circuit board. Only motor power comes back to engine.
The Yel/Wht wires to smoke fan have a plug. The other plug typically is red/black AC power to energize the smoke unit PCB. Sometimes it can be soldered wires but most are 2 pin molex.
But since it is not working, just take it out of the engine and power it up with AC on the bench. Visible inspection may show your issues. G
