I have been monitoring that for the past week or so. I have heard several VHF channels used by, I believe, the coordinators in the past but was unable to confirm the actual use in context. I do know Grand Gorge EMS had a VHF portable that was used to communicate with Delaware. I am unsure if the XB was done in the rig or if it was done on a tower.
Notes from previous observations, not confirmed to still be active:
154.355 151.4 XB Delaware Fire
154.040 127.3 XB Delaware Fire, heard near Oneonta in the past, also heard 82.5
160.215 186.2 XB Delaware Fire