I've tried an on-ground IRS alignment during a maintenance tow on a 747-400 (similar generation). Even on the straight sections with few bumps in the tarmac and minimal speed changes, the IRS MOTION message eventually appears and the countdown restarts (although not always immediately after the selector knobs are set to NAV).
If it had succeeded I beliveve that when the aircraft stopped at the end of the tow the displayed velocity would have been negative whatever the tow speed was.