Well...This is preseason interview, most likely from Aug 2018. Interesting that Nikita put on skates as 3 years old and entered in a hockey school when he was 4.
Basically, he repeated the same public reason to leave the NHL which was lack of ice time. Regarding his experience with the NHL, he said:
1. In 1915-16 season the Avto club lost in playoffs and Tryamkin's contract with Avto was almost over. Nikita knew that Vancouver was interested to bring him to the NHL and Canucks still had 16 games to play in the regular season. So he moved over there.
2. This was not about money. This was a dream of every hockey player, not just Tryamkin, to try himself in the NHL.
3. After the contract was over, he was offered new 2-year contract. Nikita did not sign it. Why? He was not satisfied with the situation. Nikita wanted more ice time, 14-16 minutes per game was not enough for him. For instance, he played 20 and more minutes last season (with Avto). Tryamkin said about his NHL season that sometimes he was sitting on the bench well rested and felt that he could play better than some other tired player on the ice, but that other player had huge contract and was kind of pushed to play more to earn his pay cheque. "And you are sitting and waiting..."
4. Tryamkin returned to the KHL to play more hockey, this was not about money at all.