I was in the same situation as you Friday, looking for the FWS control box, a DSC100 dual motor controller. I had one lock that wasn't moving, the molex connector for LA1 had fallen out somehow and was just hanging there. Plugged it back in, insured the locking tab engaged and LA1 started working again.
I found the DCS100 attached to the ceiling of the third cargo bay from the front of the coach, on the driver side, very close to the bay door. This is the same side as the FWS. The controller was under a black plastic cover that didn't have any labeling on it.
There were two black covers in that same area and the FWS controller was the under the cover closest to the cargo bay door.
2011 EXDP 4524