I don't know what the mechanisms or rules are for that, but my first instinct says that it's probably a downgrade in terms of quality of play (or lateral move at best) and probably not worth bringing him over for that.
But primarily, I'd assume it's not a great option because the USHL is usually a precursor to college, or in some cases the CHL. I don't know if anyone has ever gone from the USHL to the AHL before. And even if that somehow did happen that he were to make a jump from the USHL to the AHL the following year, it still would be good to have a Russian teammate for the same reasons I mentioned before.
I also have no idea what the CHL import draft window or timing is. If this year's import draft hasn't happened yet and he wanted to come over, I would think theoretically it's not too late? Unless there were also CHL rules that have an age restriction on imports...but even then, you would think he's still young enough?
Hmmm....?