Umpire controversial decisions: Stroke or no stroke?

This clip from EHL (found at FieldHockeyRef), shows a penalty corner where a long rebound is given and a discussion between the umpire and the defenders occurs.

1. The attacker that picks the rebound smashes the ball into the goal
2. The ball impacts on the body of the defender that was on the line.
3. The umpire blows a stroke.
4. The defenders complain that it was a dangerous play.
5. What do you think?