For example - Russian newspapers informed that after clearance to descent pilot get the clearance to the right turn, just against the mountains. If true, it could be a contributing factor. Aspecialy in case of Russian pilots. They are used that ATC have much more responsibility.
The pilots have to adopt to the rules and regualations of the country they are flying in. ATC handles every aircraft according to those rules and regs, regardless from which nation this aircraft originates.