Couple of things...
1.) The drive side cover is surely not flushed down... check the threads on those high areas (where it is noticable not sealed to the hub face) to be sure they haven't stripped (many times there are 1-2 which have stripped... I just force an SAE metal thread of slightly larger diameter into the holes).
2.) Once you have the cover tightened down, remove that chineese thread on disc brake and double check the disc side cover bolts are tight and that the cover is flush with the hub all around.
3.) Put it back in your dropouts and run it again, I can't tell for sure with that disc on the mount but it looks like the actual hub flange on the disc side has a bit of a bend in it (it appears that way in the beginning of the video)... Tightening the covers will take care of the outter wobble but if there is still runout, I would pull both covers again and check the mating surfaces of the gears are aligned properly (inspect for debris also).
4.) Almost 50% of the motors (geared) I receive from China are cover out of true condition... This is normally because they strip a few threads on one or two of the mount holes (not sure if this is automated or manual mistake)... 98% of the time I can correct the errors with larger diameter metal screws and proper cover torque... a few times the issue has been internal seating but that was usually fixed by proper tensioning of the cover faces (it forced the gearing back into proper position)... a few times the actual hub flanges have been out of true and the runout was too large to correct, I've lost 3 geared hubs that way (out of more than 70 so far).
Hope that helps...
Hey Mike, thanks for all the detailed information and great suggestions! I finally got some time to play with this new hub again, so I decided to give them a try.
I removed the screws to the side cover and separated it from the motor. All the screws appeared to be ok, and came out pretty easy. The side cover slid out about 5mm and I could tell it wasnt straight, but still can't figure out whats bent. It fits snuggly enough on the axle that I cannot make the cover wiggle side-to-side very much at all, so I know its not wobbling because of any play in the bearing. When I spin the cover, its easy to see it doesn't spin true. Either the cover is poorly machined with a bearing that was pressed in straight, or the cover is straight and the bearing was pressed in crooked.
Lightly spinning the rest of the hub showed that it still has some wobble even without the crooked side cover attached, but not as much.