I don't think TVR has much value league wide but I could be wrong. If he does, then he is a bad example for what I meant. Maybe Sonny Milano is a better example.
The basic premise being, Washington could check a lot of boxes by trading for Tarasenko now vs waiting to see if he will sign in the off season. Ottawa could take back a bad contract to get an inflated return, and Washington gets both a long-term piece and a rental. They may not want to give up assets strictly for a rental given their position in the standings.