Angry Coach at Halftime

[OHBBREF]

I have to go with Rut and Mark here.
your juristicion does not include the teams lockeroom - despite Nevada's post about using electronic media - that applies to the use of electronic media for coaching purposes specifically.
The Rant by a player or coach in a passage way was directed toward an offical, and there by punnishable.

While you "know" the comment was directed at/to you, you can not make a strong enough case IMO to justify the T. What if it is the visiting coach and he doesn't know the place has thin wall or that you are next door?

Handle it through the proper channels by filing a report - and in the second half if the coach opens his mouth in anyway that would reenforce those comments, let him have it.