Let me say that a little differently and you correct me where I'm wrong: Your Sunseeker has a Schwintek dual synchronous motor slide. You want to know where the controller is??
I don't have your unit so I can't tell you exactly where it is, but the motors are on the ends so I would look in a compartment adjacent to one end or the other. Hopefully accessible from the outside. Sorry if that's not much help.
My controller in my 2016 Stealth WA2916 was under the kitchen sink, directly under the P trap. Water dripped down that, in to the controller on the 1st day I took it out, shorted the box, and the slide-out got possessed. A few weeks at the dealer and its fixed.
Mine looks like this:
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TH : 2016 Stealth WA2916
TV : 2012 Ford F-250 PSD