Weird, that address does not look like it's been mining at nicehash according to their dashboard lookup and looking at an explorer, the last time it received funds was January of last year.
Ignore nicehash dashboard it's useless, also this BTC addy belongs to nicehash, it's really more or less used as a username, and then you withdraw your BTC to your own wallet, so the process isn't traceable on the public ledger, of course, only nicehash know which mining address sent bitcoin to which address.
OP, your miner is indeed infected, I am pretty familiar with this virus, although I don't recall the real name (I think it's called NightSwitcher) I do remember the nicehash hk, jp and the address looks familiar, so I am 100% positive.
You will need to flash the hashboard using Sdcard, do that on a separate LAN, before putting the miner back online make sure you change the password and disable SSH, after doing so, your miners will be secured to a good degree, the only thing left to fix would be the PC/phone you use to access the miners, that's where the virus probably came from.
If you want more safety, get a cheap PC (the cheapest you can get), don't connect it to the internet, and use it exclusively to monitor and configure your miners.