White has negative value at this point. He's overpaid, can't win a FO, and scores less than Nick Bjugstad. He's no improvement on what we have, AND his AAV is 4.75 for years to come- the rotting cherry on top is that the actual salary is over 5M going forward.
Tyson Jost has more value than him, to put it in perspective.
The face-offs do jump out as a negative, especially when we already struggle so badly there. The contract isn't great, but I don't think it's bad if he can serve as a top-9 center.
I'm less concerned about his point totals this year since it looks like he's been used mostly in a defensive role this year. He doesn't have a ton of powerplay time, but 2 goals and 2 (primary) assists in ~50 minutes isn't bad. It'd be good for like 3rd in Minnesota this year (which, uh.... not a high bar, I admit). Eye-test wise he seems like he's got a good shot and decent hands, so if he's been holding his own defensively on a struggling team I think it bodes well. One could say a lot of the same things about Hartman though, so maybe I'm just squinting at fool's gold here.
Jost worries me because he's only ever stood out as mediocre on some good Avalanche teams, but he also jumped into the NHL pretty young. Maybe he just takes the long way to figuring things out.
As for the value concerns, this is what happens when the GM puts himself behind the 8-ball. We can complain about lowball offers, but realistically Dumba's going to return nothing but the opportunity to not lose Soucy, Greenway or Foligno instead.