Fire 7, Camps, Admin and Field Comm all carried traffic during the fires.
The D1-D4 talkgroups are all patches to the conventional analog channels (and sound like it). You are not going to hear activity on a talkgroup unless someone is affiliated with that talkgroup on the site you are listening to, and without a real good reason to use the patch, most users are going to be sitting on the corresponding conventional channel instead. I have heard traffic on all four of the patched talkgroups, but it is sporadic and relatively rare...