Second picture shows that it dried out.

How-to-Plant-a-Tree.pdf (wsu.edu)

It’s still green further up though. Wouldn’t it start from the top down turning brown?

Poke around inside potting soil root ball to check results of your watering at any given time.

Yes that’s what I’ve been doing. Also when I scrape the bark that blackness is very moist, not dry. Almost like too much water. Which might explain why further up the tree is still green??

No tree needs water every day.

What kind of soil is it?

By digging a hole the size of the pot in clay soil, you could've ended up with the 'bathtub effect' where water sits in the hole and water doesn't drain away. The end result is drowning the tree.

I’m in Florida it was a sand, but I dug it up and mixed top soil and compost together and put it inside and around the hole. And added some mulch on top as well.

To start with, that's a lot of tree for such a small pot. No doubt the trees were very root bound when you purchased them.

Crepe myrtles like consistently moist soil conditions but also must have good drainage.

Keeping the tree(s) in a continually wet, soggy condition may have done them in.

My diagnosis would be that by adding soil amendments with the soil inside the hole and around the tree, then adding a sort of Dam around that and watering every day for six weeks with warm to hot weather conditions, you've produced an environment that causes root rot, which killed the tree or at least damaged it to the point that it should likely be replaced.

I've been told that crepe myrtles are quite tough trees and can be cut off to the ground and new spouts will grow out of that and produce new trees. Of coarse, if root rot killed or greatly damaged the tree, that most likely will not happen.

Why do you think it is still Green under the bark higher on the tree trunk, but black and wet lower?
I dug it up yesterday and I think the roots looked okay and Alive. Sorry this tree means a lot to me and I really am trying to save it. Everyone tells me something different and the nursery it came from isn’t helpful, just says more water or it didn’t get enough water when first planted and their other trees are fine.
I will Say too that I think it was planted a little lower and had sand put on the too Of the root ball that I heard they don’t like too. So that’s also why I dug it up to correct that situation. And at first I was using water that goes through our water softener system, now using straight well water now.

This is how it was when I got it.

Well, I can't believe that a tree that gets watered everyday in sand isn't getting enough water.

A tree that gets too much water will show the same symptoms as one that doesn't get enough. Wilted, discolored leaves etc.

And there's no magical remedy for a tree that's under extreme stress for whatever reasons.

Good nursery stock, correct planting practices and aftercare are paramount to success.

Even if the tree survives, it won't show any improvement overnight. It could take until mid season, at least weeks before anything positive shows.

So, If you're certain you've corrected all the variables and that it's planted at the correct depth and isn't too dry and is getting good water (when it needs it), about all you can do is wait and see. Tree have a will to live, up to a point but generally are pretty hardy.

Thank you, Jane, yes I dug it back up and I planted it up higher. I bought a soil moisture tester and haven’t watered it in a week. But I do have sprinklers that go off 3 times a week for 20 minutes haven’t had any rain. I bought some Crepe Myrtle fertilizer, been wondering if I should use it or not!

UPDATE: it stated having baby suckers coming off 3 of the 4 tree trunks!! No leaves though on the big trees or any signs of leaves coming! Is this a good sign? Do I remove the baby trees?

No, let the sprouts grow -- that may be all the umpf it's got left. Crepe myrtles commonly sprout at the base if the top is damaged or killed -- some in cold climates do so every year.