First you should verify your project to see if its setup correctly
View attachment 2246832
Then, idk if you saw the example dildo, but you have to use it as a template since it already has all the scripts attached to it. So you would go, in the project window, to
Assets>_YourMod>Dildo (red arrow) and double click on the prefab (blue Arrow)
View attachment 2246825
If you can see this, you should try exporting then, and see if the default dildo works first. I can tell you how to replace the mesh after.