[umpjong]

If the interference was as obvious as it sounds, and I clearly saw it, I would probably call it immediately after seeing that my partner was not going to make a call. There are times when a partner may miss something, and if its that obvious why wait for it to get to the crapper stage? Maybe your partner had a brain fart, whatever the case was. (in this instance he did not know the rule). In this case you either have interference or obstruction. If you see it call it...........
Had the partner made a call on it as it occurred you could then wait and offer your insight in a brief meeting.

The concept of getting the call right is not a new one...........

At the level of play cited (14 yr old) and a young umpire involved, I cant believe anyone would call fixing this a case of throwing a partner under a bus.