My only objection to the hit was that he was trying to hurt him......and he did. It's pretty grey as to whether it was illegal or not, but make no mistake that he was trying to inflict damage. There were a lot of strides taken prior to the hit.
Down by two, about a minute to go in the game, you have the extra man on the ice, and instead of trying to keep the puck in the offensive zone you choose to take the head off of an unsuspecting player.
Backlund knowing they had the extra man on the ice and that nothing is over until it's over was doing everything he could to make sure he got the puck out of the zone.
Looking at the whole picture......Dumba took out his frustrations of losing the game on Backlund. Then, when challenged for his actions, turtled against a guy three inches shorter than him. Sometimes you need to answer the bell for your actions. If not this game, he'll be asked to do it next game. Kinda the way the NHL has been for decades.
As a Wild fan, I have the complete opposite take of the sequence.
I didn't like how high the hit was personally, and wouldn't make a fuss at all if he sat a game or two for it.
But I don't have any problem with the motivations and sequance that led to the the hit and he wasn't trying hurt him, Backlund was in the middle of the O zone with a relatively clear lane to the open net. Dumba (and Brodin's) only job at that point is to separate Backstrom from the puck before he takes that clear shot, because most NHLers can make it.
Coming back from 2-0 with a minute left is a rare, but not impossible for the sake of round numbers let's say it's 1 in 100 chance. But if Backlund gets the open net it decreases to basically zero percent chance. You say Backlund knows nothing is over until it's over, the same applies to Dumba. He knows that if Backlund get's that net, it's game over. He had to separate Backlund from the puck.
As for the turtle, it was 100% the right play by Dumba. It was clear at that point they weren't calling the hit. With 50 seconds left, why on earth would he give the Refs any excuse to even things up? Turtle, take the lumps and start the 6 on 4.