What does your dolly need? 4 pin, 5 pin, 6 pin or 7 pin? All are available.
Chances are the magnetic lights use a 4 pin.
As stated above, you can get a device that has both a 4 pin and a 7 pin socket, so you can plug both in at the same time. If both your dolly and lights need 4 pin plugs, you could change one to a 7 pin.
The illustration above is for a 4 and 6 pin. Following is a link to a sample 4 and 7 pin for illustration. They are available in a number of places.