We need a way to silence downed enemies

Maybe a bit brutal, but a bullet to the head of any downed enemy (maybe only after they have VOIPed?) should disable their ability to proximity VOIP.

You just wiped half a squad, you're holding a corner over their bodies waiting for the revives to come in and you hear them yelling, "He's in the second story window on the-...!" BAM you shoot the VOIPer in the head mid-sentence so he can't give away your position.

Too much?