Boarding kill stealing

When you see someone board a tank and plant their nade wait a second then shoot the tank once and you get a free nade kill. Why is this a thing?

Idk. Ive “stolen” kills (not purposefully) and had my kills stolen on tanks…

Same here plant a grenade then end up with a tank destroy assist. but its cool no biggie. it is a little frustrating cause I’m trying to finish the tank destroy commendation and I’ve been stuck at 2 away for like a week.

Pretty sure I have that happen to me in BTB, have gotten a nade kill. If I recall correctly I wasn’t even shooting the tank when I got the kill but I was shooting at it, then stopped when a team mate boarded it and planted a grenade. But I got the medal. Seems like a bug.