Oh that is FABULOUS! These are very lucky kitties - they have NO idea just how spoiled they are - and are going to be!
Oh, I was posting at the same time you gave such a lovely long update. I was laughing too hard at Miuku trying to knock over the now sturdy scratchy post, and especially Mouku attacking Miuku's twitching tail!
Mouku starts to get used to me a bit, I guess, when in dark room he now runs after treats when I toss them, he did lie on sofa like he would own it, very relaxed when I came in, Miuku could be only heard of, he did battle with himself, I could hear him scratching mattresses behind the curtain as he probably wanted to get treats too, but as it was now bit earlier he was not yet so confident as Mouku was, I was there 45mins early as I need to do many things before I go to sleep.
I could see him peeking under the curtain, just barely as it is so dark in there that it is difficult me to see, but then he did hide again.
Miuku and also Mouku do scratch things when they are facing situation where they would like to do something, but are bit too afraid, it is also sign that soon he will try a bit and finds there is no real danger, so scratching is good too and there is nothing they would not be allowed to scratch on, however they seem to understand quite well to scratch stuff that can take scratching and also their post is very much used there.
I think they now race to find as many of those treats possible competing which one gets more, at least there is lot of jumping and running going on