Since 2013, 5v5 save percentage:
Enroth 92.3%
Kuemper 91.9%
Ward 91.2%
Dubnyk 91.2%
Backstrom 90.0% (dead last)
Adjusted 5v5 save percentage (takes into account shot location):
Enroth 92.4%
Dubnyk 91.1%
Ward 91.0%
Kuemper 90.9%
Backstrom 89.5% (dead last)
I'm not looking at this season's stats because of sample size.
Of the rumored options, Dubnyk is a below-average goaltender, neck and neck with Ward, and Backstrom is the worst goalie in the league. So Dubnyk is a better option at least as a backup.
Kuemper's save% is average but adjusted dips to well below average. So...I don't know if there's anything to that. He's clearly not ready for a lot of work.
Even without stats, Kuemper is not starter material because he's not mentally strong enough to rebound, and Backstrom is just completely done in the NHL.
If you're talking about the 3rd rounder being too high, I can agree or I can play Devil's advocate. Fletcher has a lot invested in Mike Yeo. He's built the team to play that style of hockey. If you think goaltending sank the Wild, then this is your litmus test. You can't evaluate Yeo or the team otherwise.
I think Dubnyk will be an average goalie where the Wild have got well below average goaltending and to an extent even worse luck. I don't think Dubnyk will save the season, but I think he will stop the bleeding and hopefully give the team some good things to build on.
As for tanking...can't help you there. Wild were never going to get a top two pick. Prospects from the 8-12 spot are a crap shoot and won't help the team for 2-3 years. I'd rather see the young kids (re)develop.