Did some cursory digging (but I'm phonefagging) and could find no mention of a cross being on the floor of the Rotunda. Wonder if it was just added, or has always been there and just covered up?
The Witch is dead?
KYS is part of Chan culture, but I too can't bring myself to say it as I've experienced the devastation of suicided family members. That said, Anons here who say it don't truly mean for other anons to do it, it's just an expression. Like "jump off a cliff", they don't expect the person to really do it. Not defending or criticizing either side.