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Perhaps the real question is whether it makes sense to try to control the size of a shrub that naturally grows to 15 ft by 15 ft. Pruning should be done in the dormant season as the bush flowers on wood made in the new season. Use heading cuts - cutting branches back to where a side branch comes out that is 2/3 the size of the branch being removed. Alternately, remove the branch at a main trunk. Cut at the branch collar or 1/4 inch above a leaf bud. Indiscriminate cutting will yield numerous suckers, watersprouts and weak terminal growth. Don't remove more than 1/4 to 1/3 of the overall structure during any one year. Remove suckers and watersprouts when they appear.

Yes, this can take a year or two, and sometimes longer to flower. With some patience, this tree will bloom profusely with little care. This article will give you more information on these: https://www.gardeningknowhow.com/ornamental/trees/smoke-tree/growing-smoke-trees.htm

This will only need watered when the top two inches of soil are almost completely dry. This will avoid any fungal infection and ensure that it remains moist enough, but not dry or wet.

This article will give you more information on the care of these: https://www.gardeningknowhow.com/ornamental/trees/smoke-tree/growing-smoke-trees.htm

I'm also in MN and we had a brutal winter!
Smoke Bush are hardy in zone 4a, though I would say we were well below normal for most of the winter. Your shrub may not have been able to sustain the temperatures.
Check the branches; to they bend or snap off and break?
Prune away the dead branches. It's possible the shrub roots could still be alive. Continue to give it time and if you see not signs of leaf out, it's time to replace.

I'm watching a few things in my own garden, but willing to give them more time!

Good luck!

I will send this to our Editors to look at.