He adjusted his Game to a smaller ring and the new Interference rule, plays in his Cards. Since Dadonov is a excellent skater and fast he can play the rush Game also in the NHL.
In addition they gave him a Linemate who set you up all the Time as best he can. So comeing from the KHL playing with excellent Linemates, he comes into the NHL and find the same thing.
And in addition it also helped, that a lot of Players on the Team, speaking Russian, what helps you to feel more comfortable.
But dont forget it took him 2 Month to adjust his Game, the first games with the Panthers was not so excellent as it is now.