lol I told you how, it was on a fresh faced 50 in PvE gear. Don't disregard my gear either. I am fully mix/maxed EWH too, the only thing I never ended up getting was a PvE armoring for my belt, I used a Black Hole body armouring instead.
As a healer, I've seen people doing this recently on Repub side. Yes, people have gone into 50 PvP with their mixed bag of 40-50 leveled PvE armor (I've even seen someone with level <30 stuff on before). It's rare, but I've seen it. I don't play imp side, so I don't recognise their gear visually to notice if they were in PvP gear or not, I only assume that they were not due to the fact I smashed them with a High Impact Bolt and their health just vanished.
You claim it's a bug in the score board, but I've played this game since launch and have never once seen the scoreboard bug out. I've seen it not count biggest hits or heals (this is due to over damage or over healing) but never randomly fabricating something that "didn't happen".
But that's okay. <3
I'm curious to see other screenshots of things that you disregarded, just out of curiosity, because I've never seen the scoreboard bug.