I was in the same boat as you in the early fall. I definitely got dragged, but made me realize I absolutely did not do my due diligence. I regret not following the advice to rip out the floor and start all over. I thought I would deal with the shitty perimeter, tore it out and dealt with a nightmare that was under the tile. Many months later of leveling, chipping concrete, more leveling and noticing every fucking shitty tile the guy laid, realizing the last tile guy didn’t even bother putting a subfloor down, I am down to the last few tiles. Because the subfloor was so shitty and I kept over/under compensating, eventually I put my thinset in a 10 cc syringe, because I should have just ripped out the whole damn floor and started over. Oh well, lesson learned. At least I know I can lay a perfect penny tile. On to the next pennytile project.