Ninja looting? Reportable?

Hi, recently I was doing a dng and the tank (a DK) took an item that didn't fit his role/class, at all, as I said, he/she is a tank, playing and filling that role in queue. One of the other members of the party needed that item, as it suited well with our builds (I think he was a druid healer, and I'm a Balance Druid), as it is a caster specific item, not a tank one... The thing is that this DK tank rolled "need" for the item, when he/she didn't... It didn't suit at all with the build/class/role...
I don't know if the guy is new to the game or what (I am, and got kicked of a dng group BECAUSE OF DOING THIS EXACT SAME THING), but he didn't know at all the dng we were inside, we had to explain how to mount the dragon to go to the platforms, etc etc.
So idk if it was on purpose or what.
What do you think?

Reporting Players [Updated: May 22, 2020]

Your screenshots proves absolutely nothing, nor would those screenshots be valid in a report. Screenshots in reports need to be original/unedited. Even a cropped image won't count.

You can remove names and screenshot link. Forum isn't the place for reporting players to begin with.