Upon closer looks at your video and pictures there is a chance that this Gordon has been repaired and gone into quite a bit. The stripped screw heads is the first indication and up closer inspection it looks like he has been re-wired also as I don't think (although I could be wrong) that Tomy used two red wires between the engine and tender plus they look to be a larger gauge wire. I wouldn't think any of this would affect the inclines as in the video the motor looks strong as the wheels are turning and don't look to be slipping.
I would really like to see the inside of him as I suspect repairs and possible missing parts/weights. Have you tried to use a small flathead screwdriver to loosen the stripped screws?
I would really like to see the inside of him as I suspect repairs and possible missing parts/weights. Have you tried to use a small flathead screwdriver to loosen the stripped screws?