So I encountered this playing the PS4 Beta on 4/8 at around 23:00 PST. Not sure how this was accomplished, but the guy was un-killable. The only thing of note is that he had 1 death at the end of the match, possible that he had to die to achieve the bug. He was taking hits for 23 damage, but the health bar was not moving, despite being hit by base turrets.
I had the same issue with a player in a match of Incursion, also with only 1 death at the end of the match. He had 4 members of my team wailing on him, but they didn’t make a dent in his health.
My friend does have a video of the incident, but I unfortunately don’t have access to it right now to post it to this thread.
Moved to the bug report section. Thanks for your feedback!