Which Crews or Team Weapons
AT guns, HMG, and Mortar.
Which Units scored the Kills
PM-41, HM-38, KV-8, Universal Carrier w/ wasp, Katyusha. There are others, but these are the ones I know for a fact have done it.
Which Faction?
So far Soviet and UKF confirmed.
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To clarify, this only occurs in the After Action Report. The in-game kill count shows infantry kills when you wipe a weapon crew.