If that nut were loose, yes your bearings are probably toast... but it may be worth playing with it by tightening and turning by hand etc.... Worst case, you can find a used one pretty cheap. Check the flea market here, and try the IBMWR fleamarket... there is usally a lot of stuff on there, with some good folks. I would use eBay as a last resort for something like this, though there are a couple of good bike-breakers who know their BMS stuff...you can try to contact them to see if they have anything that isn't posted.
Yes sir, Thats the bad boy..Nut folded the treads on the shaft , and the shaft wiggles . Shot