Baseball fields are private venues. I would assume as long as fans aren't there that law wouldn't apply.
Restaurants and bars are private venues too. So are most health clubs.
Yet, by the end of the week I guarantee there will be a statewide mask order in place for them.
Restaurants and bars might not be a good parallel, but a health club is. It’s easy enough to be socially distant in that setting provided equipment is far enough apart.
Additionally, several states are in far worse shape than Minnesota. If the governor of California gives it thumbs down, there are 5 more teams scrambling for a place to play.