Just to dial it back a bit...
is it possible that Peters sent Lomberg out hoping he would exact revenge on Dumbass? Yes.
Do I know for certain that was his intention? No
Do I think Peters told Lomberg to go out and try to hurt Dumbass? No
Am I glad that Lomberg did what he did? Yes
Do I think Dumbass's hit on Backlund was clean? Questionable and there's certainly room for debate.
Do I think that type of hit was necessary? No. Not with 53 seconds left in the game and Minnesota losing 2-0. The hit was meant to punish. Mission accomplished.
So Dumba's decision to hit had nothing to with the fact that Wild's net was empty, they were chasing, and Backlund was about to take off to score an empty netter on Dumba's point of view? Did Dumba have other viable options? If he did, I'd like to hear what those were. Poke check? Probably the most viable option, other than hitting but risky as the puck could've easily drifted to another Flames' player.
If that was Dumba's first ever open ice hit at any level, I would buy that "he was trying to punish" theory. But no, that has been Dumba's bread and butter and go to move since he was a junior. Sure, he isn't lighting people up every game because that's frigging hard to do, but if he has a chance to make a play via either hit or poke check or <insert any defensive play here>, he's going for the hit.
And why punish Backlund after so much time has passed? The Wild has more than a few capable bodies to toss in the rink to either hit even harder than Dumba or fight. Your theory just doesn't make any kind of sense.