Strike or HBP ?

[AtlUmpSteve]

Sounds to me like you got it right. Every rule book and umpire manual that I know of says the primary determining factor that you must use is if the batter made an attempt to hit the ball. That alone supercedes any other discussion of the bat moving, or how far, or did the wrists break, etc., etc.

Since both you and your partner judged there was no attempt to hit the ball, everything else the defensive coach had to say had no basis; just trying to get a call.