Tagging /u/TreyarchCM in case they see this, I made some observations today and I might know the culprit - I think it's the Mic Drop gesture causing the problems. Before the patch it did not have a voiceline, and the gesture itself was bugged as on player models the microphone would appear over the player's hand before it was dropped. Today in testing, I noticed that there was a new voiceline ("Boom: Crushed it.") which shows that so far this is the only working bundle gesture, and the graphic error has been resolved. On player models now, I can see them holding the mic and actually dropping it.
I also noticed that with the exception of Crank Job, all of the voice lines seemed to work appropriately in Warzone, if that makes any difference.