Other ways to handle it?

[Andy]

In this scenario, I don't see how an ejection could be avoided, if it was me it would have come sooner.

You are absolutely correct in that the delayed, then weak out call was the start of the trouble. Since you knew your partner was a rookie, you might have accompanied the coach when you sent him to your partner. Just a suggestion, let your partner handle the conversation as a learning experience, but be ready to step in if necessary.

The coach continuing to ask about the play after the meeting should have been met with "Coach, the play is over the call has been made, and you have received your explanation. Let's play ball!"

The first comment from the scorekeeper about being the "worst all year" would have been the last. Since he is in the dugout, he's team personnel, this was a personal comment and a scorekeeper ranks lower on my list than an assistant coach. Ejection - right now! If he keeps going, my instruction to the head coach is that your scorekeeper has been ejected and guess who's next if the scorekeeper doesn't disappear real fast.

There are just times when an ejection is necessary - from your description, this sounds like one of 'em.

Needless to say - a very thorough post game with your partner was also necessary!