If you don’t already have a solar charge controller installed that you’re not aware of, it’s most likely somewhere near your converter or batteries. I know ours has two loose wires run to the same area as the converter (under the bed for us). If I recall correctly, ours has Orange and Orange/White 10ga wire running from the roof gland which is in a loop just sitting loose and that jives with a few other posts I’ve seen for various models.
Knowing Thor, there’s good odds it’s probably the last place you’d ever think to look.
If you haven’t found it already, there are two good resources I know of for mobile solar which might be helpful:
https://explorist.life
https://www.mobile-solarpower.com