I get the argument that it's a conflict of interest for him to be working as an assistant coach for a KHL team, and simultaneously work as a scout for an NHL team that just poached a top player from his KHL team. Though if the KHL team in question is really about to fold, then that's not really even an issue, and that would explain why the KHL team in question didn't care about Namestikov taking the job, or about Soshnikov bolting to the Leafs. But yeah, trying to argue that it gave them an unfair advantage over other NHL teams is nonsense. Like you said, any NHL team could have hired him---boo hoo for them that they didn't think of it first.
Anyways, nice hire by the Leafs. Russia's definitely a market we should be looking to exploit. With the ruble having fallen to "toilet paper" levels of value, and with so many KHL teams on the verge of collapse, we're probably about to see an influx of Russians into the NHL that we haven't seen the likes of since the early 1990's.