Brock Boeser scored twice, Jake DeBrusk had a goal and an assist, and Demko made 24 saves for the Canucks (17-10-8), who have one win in their past five games (1-1-3).
“Honestly, it's pretty devastating,” DeBrusk said. “We should never be losing that game, let alone letting it get to overtime. But it just goes to show, there's a couple bad bounces and a resilient team over there. You’ve got to give them credit, but it just reinforces the focus we have to have no matter what the score is. ... Anytime that we have a two-goal lead there late, that's got to be automatic.”
Vancouver played without defenseman Quinn Hughes and center Elias Pettersson, who are each day to day with an undisclosed injury.
“We were pretty good for 55 minutes,” Canucks coach Rick Tocchet said. “We needed a couple of composure plays. We didn't get them. I'm sure that some of the guys feel bad. And we did a lot of good things. ... We needed somebody to calm the waters down a little bit."
Schwartz made it 4-2 at 15:15 of the third period, scoring with a shot from below the goal line that banked in off Canucks defenseman Noah Juulsen.
Dunn cut it to 4-3 at 18:48 with Grubauer pulled for the extra skater. He stole a clearing attempt from Carson Soucy in the slot and quickly shot over Demko’s blocker from the right hash marks.
Schwartz then scored 22 seconds later to tie it 4-4. He drove to the net and converted his own rebound in the crease while falling to the ice.
It was his 500th NHL point (207 goals, 293 assists) in his 767th game.
“Jaden, for his 499th and 500th point in the National Hockey League, stepped up at an obviously critical time in the game, critical time for the team,” Seattle coach Dan Bylsma said. “The second goal gets us back into the mindset of where you have a chance to win this thing, and then we score the third goal, there's 1:12 left on the clock, and the mindset of him taking it to the net, going to the cage and doing whatever he can to get us the goal, it was huge.”