Clarification please

[DG]

You don't have to verbalize an appeal if it is apparent that the defense has recognized that a runner has left too soon and can be made out by throwing the ball to base he left too early from. The action of the defense is considered an appeal, and especially if it is obvious to everybody.

Prior to the play the umpires probably signaled each other that a timing play is possible, with runner on 2B and 2 outs, but the play more likely to result in a timing play is the runner on 2B scoring as the batter is thrown out trying to stretch a single into a double. But this is nonetheless a timing play, run scores.