Definitely full coverage with the thinset. The issue with "replacing" tile is the effect it has on the waterproofing. If the tiles were bowed they should not have been used. Is there lippage? Or why are all the tiles tagged that are tagged?

Yes, it is lippage. That is the word I was struggling for! I went to my parents house to check out the install on theirs today. They actually used the same tiles a year ago but a different installer and they had only one tile with a slight bit of lippage but within a reasonable amount. Here are some shots of what mine looks like on that one wall. The first picture is shot from below looking upward and you can see how the tiles are jutting outward on various ends. Ugh. So redoing the whole wall is recommended?

Yes and unfortunately your "tile setter" is making excuses already so be prepared for push back.

Thank you! He said he would do whatever I wanted and I just wanted to make sure I know what is the right thing to request. It’s not an inexpensive job by any means and I am not planning on moving anytime soon so expect this to last at least as long as the original build did which is 20 years!

As they are large format tiles, most likely they are bowed, That is why the manufacturer most likely recommended no more than a 33% offset, rather than the 50% that you used, Even better would be a stacked bond.

You need to hire someone new, unfortunately. If this guy knew how to do the job correctly, he’d have done it the first time around.

Who specified the offset & who supplied the tile?

If the homeowner bought the tile and dictated the offset, I would not fault the tilesetter.

We picked the tile and the tile gallery designer suggested the layout. She’s been with this place and selling this brand for years. Same person who set up my parents with the same tile and design. Contractor ordered and then supplied the tiles. I am not married to any layout and I expected a quality result. If I had been given a heads up on any potential issues, I would have gladly sacrificed any pattern for a quality result. I relied on experts to guide us. It’s not like I went to Home Depot and did this myself. It’s literally been the perfect storm of stuff going wrong with the project unfortunately.

What does your contract's "detailed tile scope" say about industry standards to be met and followed?

I ask becasue there are industry standards for alottable lippage and plane specifications Set forth by the TCNA for just this reason.

The TCNA standards that Mint Tile refers to will also address minimum acceptable mortar coverage for a wet area which is 95%. It appears spot bonding was used judging by the photo's which is never acceptable. The minimum 1/3 offset it also specified to minimize lippage on large format tiles. Large format is any tile with one edge over 15". The manufacturer often stamps this on the packaging. The Tile gallery designer may have steered you wrong and the installer is clearly not qualified. Keep in mind the manufacturer may say 50% offset is OK. That would take the designer off the hook but not the installer.

The Homeowner's Guide to Hiring a Qualified Tile Installer (ceramictilefoundation.org)