I can confirm the same on a different circumstance.

Basically what I did was:

• Place a vehicle on a hill slope
• Place a mortar on the other side
• Order the mortar to fire 3 round burst on the vehicle

The three of them hit the vehicle, two passengers jump out and one dies as the vehicle explodes into flames. Then the other starts twitching or looping through a strange animation.

Upon inspection (coming in closer) the player character starts twitching as well. Moving away and ordering the AI passenger to move away to a specific spot removes the problem.

Don't know if this might be related, but upon mortar fire, the player character was affected by one of the blasts (not hurt though).

I have also captured the whole thing and can provide the video if required.