Odd, I don't remember any PKRuS tagging, but I may be wrong. It can't be all of them that's for sure. In my personal opinion, a PKRuS tag is no big deal and should be put up anyway since they're so rare, even removing the PKRuS first if it's questionable.
I honestly have no idea where the Makuhari Mews came from, I've had them on my PC a long time. Only source I can find is the github, so maybe see what @Sabresite has to say.