The pH is extremely high for azaleas, and it is going to take a fair amount of work to fix the situation. To the point that the usual recommendation is to find something else to grow that isn't as picky.

The soil acidifier you have should give application rates. You are aiming for something like 5.5. Sulfur, the usual acidifier, isn't nearly as forgiving as lime, which goes the other direction. So be careful about applying more than the instructions say at one time. This is going to take several years to fix, and then will require regular maintenance applications.

And you have planted them in the hottest possible spot. Not great for an azalea.

Since making that post/taking those pics, I have fed it some holly tone and soil acidifier. It has started flushing out new leaves (see pic). Should I wait to see what these look like or should I go on and transplant them anyway?

Southwest wall and no shade, so full-strength hot sun from noon until nightfall? Hate to say it, but I think it's a sunlight issue as well as soil pH. I'd transplant them now before they decline further.

Thanks for the replies. I will move them. So the next question is...Do I move them to a new spot in my landscape and, if so, what kind of amendments to the soil do I need to make before/during/after the transplant? Or, do I move them to a container for a time period so that I can better control the growing medium and improve their recovery?

Can you do soil tests in different areas and see what numbers you get ?

I can. But I assume it will all be close to the same, since all the areas around the house have been backfilled with the same kind of dirt.