1 . Yes, it's jambler.io partner website.
Sorry but I can't find your Mixdream anywhere on Jambler website page with list of partners, and people should wait someone from Jambler to confirm this partnership.
There could be some mixers not released on their website, but I would like to see some confirmation first.
https://jambler.io/mix-coins.php2 . Fee is 3.5% ,that is not more than other websites, we use top level anonimization of jambler service.
I see that recommended commission fee for mixing on Jambler.io platform is 2% and some people don't always need ''top level'' mixing.