Dugin’s the premier geopolitical thinker in Russia. Putin puts a lot of stock in his opinions. China, probably not so much, but where Russia goes, China will probably follow.
As for how stupid they are to believe that Muslims won’t turn on them, that is true, but you must remember that Russia began as a traitor state, appeasing the Mongols and collecting taxes from their fellow Christians on behalf of the Muslim overlords.
I did not know this.. But, I would assume, they have a LOT more to lose now then they had back then... (?) Certainly more military power and available resources.....maybe.