First of all, I would like to say that this trade addresses both team's needs, but I am unsure of the value. Maybe one side needs to add/subtract.
--Minnesota--
By making this trade, the Wild are able to solve their expansion draft problems by being able to go 7-3-1 because they don't need to protect Dumba. Therefore they protect 7F: Miller, Fiala, Jeek, Foligno, Sturm, Zuccarello, and Hartman if Parise waives. For 3D they will protect Spurgeon, Suter, and Brodin. Kahkonen in goal.
In Miller, Wild gets a first line centre that they desperately need. In his first season with the Canucks, he put up 1.04PPG and this season he put up 0.86PPG! In addition to his two-way presence, Miller will slot in nicely with the Wild lineup and be hard to play against every night. He can play whatever role they need him in, on the PP or the PK, Miller excels at all aspects of the game.
--Canucks--
By making this trade, the Canucks have an easy 7-3-1 protection list. 7F: Petterson, Horvat, Boeser, Greenway, Pearson, Motte, Highmore. 3D: Schmidt, Dumba, Myers. G: Demko. Notably left unprotected is Gadjovich, MacEwen, and Lind. Gadjovich and MacEwen are at best 3rd line grinders so I doubt Seattle takes them so I think they take Lind which is ok. He hasn't really shown his potential in the games he has played this season (especially playing with Pearson and Horvat) so I don't think he'll turn into what Alex Tuch turned into for Vegas.
After the trade, Canucks cement their top 6 with an excellent shutdown line as well as a replacement for Edler because I think he will be sheltered into a third pairing role for maybe one more season. Greenway will fit in nicely with Horvat playing a 200 foot game and Dumba will fill in the hole at defence alongside Schmidt and can be our quarterback for PP2.
Miller is the 3rd C in your depth chart (Pettersson, Horvat)... Correct me if I'm wrong, but I don't think he is a 1C. He is more suited to be a winger imo. We have a logjam at both wings, so paying that much for another top-6 W would be idiotic for us.