What talk groups were you hearing? I'm hearing nothing like that in the Richmond area.
It was a combination of things. First off I started grabbing RIDs back when DGIF wasn't encrypted. I also was grabbing RIDs off the CR units who would pop up on the VSP channels which were what they were using for comms for the longest time. They seem to have given up their DCR channels.
Also during that situation the units were also operating on the Alleghany Warm Springs analog repeater communicating with the county sheriff.
So as an example CR931 would tell Allegany he was going to inform their dispatch of something. Then immediately after that DGIF 4 would pop up with traffic. The RIDs would be for CR 217 and the DGIF dispatcher. Put two and two together and you could figure it out. DGIF out here are all encrypted 99% of the time though.
Add in that the 400 DGIF unit that was identifying as a 900 unit on the county radio and DGIF was referred to by name by the county dispatcher it made it easier. The officer used to be an Alleghany sheriff deputy who went to DGIF and now is apparently a DCR officer.
Sorry it took so long to get back to you. Somehow I missed your question.