According to Pierre LeBrun, the path the Blues take with Vince Dunn is still undecided.
In our Mock Expansion Draft, the Blues traded Vince Dunn to the Sharks for a 2nd round pick. Trading him still feels a likely scenario. There are presumably teams interesting in grabbing another defenseman, including the Rangers.
If he’s left unprotected by the Blues, he would appear to be an easy claim for Seattle.
The third scenario LeBrun mentions is protecting four defensemen, including Dunn. This would mean the Blues could only protect four forwards, who I would presume would include Ryan O’Reilly and Jordan Kyrou. That means the Blues could only protect two of Brayden Schenn, Robert Thomas, David Perron and Vladimir Tarasenko. This seems the least likely scenario of the three.