Sound like another 400SM ICE Power supply failure to me. Connections do not matter at this point if the dip switch on the Pamp8-100 is set; power mode is set to on. The fans should be running and the 1-8 Blue Led's for the channels should be on as well.
I am using the Rotator Mount with another version Samsung Qled variant and the rotation control was added in a update last year. Control done via Programming;
Version 209
Fixed DRIV-8134 (DRIV-8569): Serial control not functioning
Fixed Color buttons with Network control
Added Display Rotator Control device specific command
I have a spare, where are you located? Alternatively can order part number below;
https://www.mouser.ca/ProductDetail/Molex/39530-0004?qs=cJvWYcaovXzY3zXnMJaAzw%3D%3D
Press the power button and select restart then hold down the back button until it the "welcome to Halo" appears.
Should see the the Control4 Snap/AV logo flash on/off a few times before that happens though
Give this a shot from this thread, Only ever came across 1 unit that never took a re-flash. Saved at least a dozen for locals in my area thus far this year.