[Mark McLeod]

Could be electrical, could be programming.
We'll need details of how you wired them, which PWM is used for each, and confirmation that your code is using the correct associated PWM.
Closeup photos would be nice, too.
Details of the code, too.

If the Victors were blinking then stopped when the robot was enable, that means they are communicating successfully over the PWM cable, the code has opened those PWM outputs, the Victors are wired and receiving 12v power, and that they are being ordered not to move (or not to move very much).

It doesn't mean your code is telling them the right thing to do, the joystick is on the USB you expect, or that the electrical system downstream of the Victor is connected correctly.

If you have a joystick commanding them, then you should be able to get the Victor light to go green or red even if it's not working right or sending power on to the motor.