Did you take the motor off, or hold your spark in place?Great post, which prompted me to write my first, having only had my Spark (first drone) for approximately 3 weeks.
I stumbled across your post when I had exactly the same problem, so I did as you did. Just finished and tested in the house actually.
I didn’t use a hammer though, but instead I slid a small hex socket over the shaft and then used a very small vice to drive the shaft further through the motor casing. I can see from your pictures your shaft was misaligned with respect to the inner race of the bearing. Mine was slightly different in that I could see the outer race of the bearing protruding too much through the motor casing, but same result anyway.
Looking forward to testing properly tomorrow in the light of day ...