Opinions please

[Chess Ref]

Partner and I had a minor disagreement on this play.
I'm BU. R1 on 1B. Batter hits a gapper to right field. I follow the batter into 2B,pretty close play. Then F6 comes up throwing to 3B for a play on R1 ,who slipped rounding 2B, a rocket of a throw that missed F1 who was at 3B. The throw then strikes the coach in the 3B coaching box.

He did make a nice effort to jump out of the way but the throw nailed him in his foot. We had to hold up the game for him to regain his composure.

Partner who was at 3B for call immediately came up with "Dead ball". So play stopped. I thought we should have continued play but he believed the coach was a form of detached equipment and hence it was a blocked ball. The ball only rolled a couple of feet so it didn't really have any effect on play but was wondering what others thought about killing the play ?