Several points:
1. Although you can manually crank a slide in or out it is not a simple thing to do. Lots of effort to get it moving manually.
2. Motor is visible from the basement or from inside under the bed if it is the slide that moves the bed.
3. Confirm you have power to the controller, as it could be a fuse.
4. If your controllers for the slides are the same, you can swap controllers wiring to see if the controller is bad.
5. Not sure about REV center in Colburn, but expect like Decatur, if you drop in on Mondays they work you in some point during the week.
6. There are also Mobile RV mechanics that come to your site. Local campgrounds are a source for recommendations.
Feel free to contact me if you need clarification on things, you can find my info under the officers tab.