Apparenly judging from my former report, he was labeled as CLEAN.
Maybe the BF4Cheatreport and BF4DB snapshot are not convincing enough with most of the battlereports showing that he's using sniper.
So here's some specific battlereports when he didn't use sniper rifles.
http://battlelog.battlefield.com/bf4/zh/battlereport/show/1/963839730135124480/354477296 33K 15HS. He did get some kills with M40A5 but no sniper ribbon.
And he was very bad with sniper and assualt rifle in January 2018.
http://battlelog.battlefield.com/bf4/zh/battlereport/show/1/947726825766225280/354477296 105 shots are fired, 15 of them hit, 7 kills, 0 headshot, in 25 minutes, on the map Dawnbreaker, 0.28 KPM.
And in February he suddenly got gud.
http://battlelog.battlefield.com/bf4/zh/battlereport/show/1/963819315882936832/354477296 17 shots are fired, 7 of them hit, 7 kills, 6 or 7 headshots, in less than 2 minutes, on the map Golmud Railway, 7 KPM.
There are plenty of other sniper battlereports to compare with. A little weird if you ask me.