Got the motor back via UPS. I also talked to the person who repaired the motor. I found out my motor was not damaged by water. Instead, one of two things may have happened. First, there may have been a factory defect in the "core" piece of the motor. Second, the "core" may have failed due to driving habits. Turns out, if a motor has lots of current but can't move (maybe it's on a hill) then the windings can overheat. When that happens, some windings might short and the commutator can warp too.
So, to play it safe with the motor, I have changed my driving habits a bit. First, I avoid "flooring" the throttle just to show off, especially when going up steep hills. I find cruising at 30MPH keeps up with traffic yet doesn't lose too much energy due to wind resistance. Since doing these simple changes, I've discovered my range across town has increased dramatically.