More watering.

Really.

Been there - done that.
Are we talking daily, 1-2 buckets or more?
No one told me this tree requires more water than others.
We planted all new trees at the same time, including Crimson King, several pines, etc. We had a very wet summer last year and it looked the same. And was the only one.
Sorry, I think there's something more going on here.

Mine drooped for several years after planted, then finally quit doing it. During this time they kept growing.

Thanks, Ron. I was hoping that was the case. Mine is growing well. I will hang in there.

If the tree has much size to it 1 or 2 buckets of water won't be enough. Dig next to it and look at the soil.

my Red Maple can't get enough water, I can leave a hose going on it for hours a day, several days a week, and it just wants more and more!

I have a Red Sunset that was planted last October. It has wilty looking leaves also and they are a light green color.

Is this just a phase the tree goes through due to transplanting?

Maybe I will try to water it more often.