Ok that's where I got confused by your question: a Talkgroup in DMR parlance if a Group.
The closest i think you'll get is to use DMRDecode in parallel (as it does show this information) and if necessary configure the file-naming convention you use for the wav file recording / DSD+ log file to include a timestamp, to allow you to do a manual retrospective lookup of the info you're after. I guess there might be some clever way of scripting a merge between the relevant logfile info from DMRDecode and getting this to write maybe to the .srt file for the wav recording (and befoe you ask, no I haven't a clue how to actually do this)
Jim