Hey Kevin, welcome to ATP
Did you break up the root ball some and spread the roots out when you planted the shrub? Was the root ball good and moist? Sometimes if the potting mix in a pot gets very dried out it's hard to re-hydrate it and the water added goes over and around the root ball.
Amazing with all the rainy weather you've had, that plant hasn't rooted better. If this wilting keeps up, I would at least dig a small exploratory hole down beside the root ball and see if you can see what's happening.
If you get a run of hot weather now, I think a piece of shade cloth or something else to shade that baby might be a good idea.
