Hi all. Thanks for the warm welcome and advice. Note that this is a camper, not an RV (if I'm saying that right).
Update:
So the buddy who sold it to me is stopping over later today to drop off the awning and propane tanks. In the meantime, here's a video of what's going on...
https://youtu.be/p1S2i2Y1uJ8
I love tinkering, so determined to get to the bottom of it. The good news is that it will manually open, with enough patience and redneck ingenuity.
Next step is test power at the motor. If no power, I'll trace it back. If it does have power, maybe the motor needs to be tested.