Very possible they were on Tac2 but calling it as METCOM as part of a drill. Hear this done on fire ops channels during training all the time. Protocol calls for contacting on a named talk group so they sub an agency talk group to be that channel but speak the script as if they are on the called for talk group. During the Search for the shooter in the LODD thus summer METCOM was one of the best sources for info. The first radio traffic I heard on this was on METCOM with DCC calling for assistance on a reported officer down.