If the site goes down as soon as the donation goal for October and November has been fulfilled, I smell something fishy.
The site started having problems around late October and then they started increasing the costs every month since this year started each month, but then as soon as the importer gets patched they dissapear.
I bet they shut the whole thing down once the importer couldn't work again, they realized they couldn't milk the people of money anymore since they increase the donation goal each month and the site doesn't get better, I can argue it has gone worse, so they asked for 2 months pay and peaced out.
Them going without an announcement or a way to be in contact with just confirms my suspicions even more, Kemono.Party worked closly with the Yiff.Party guys and they have a Telegram channels, and they stopped responding to people since the start of the month, when they used to answer you almost right away.
They just baged their last score and peaced out.