How much does it bother you? You are the only one that can answer that. You can't add a border at this point. Perhaps you can add a pencil under the cabinets straight to counter and take the herringbone pattern to the bottom.

I don't think this is done right at all. Not sure about communication but I always lay out a specific design plan and then go over it in person with the tile person to avoid these type problems. I think it has to be removed. Verbal communication, especially if there is language differences between people. Hope you can resolve this because every time I looked at this, all I would see is that cut out and totally wrong placement. It isn't even centered. They could have done a straight line of tile under the hood and one straight line below. Then a simple boarder of the subway and the center portion the herringbone. The space is actually too small for this tile to do a proper herringbone. Need longer tiles. So, guess it just depends on what you can live with or negotiate with the installer. The quicker you get this down, if that is what you decide, the easier it will be.

herringbone requires precise measurement to get both sides equal. as you can, the left is diff from the right.

Not to mention the top and bottom are different. It should look like this and it should have a border. (you can rotate this to get a vertical layout)

ou need to find the middle of your square accent box, and then do a 45 degree angle on your tile to find your starting point. this way you end up w/symmetry on all four edges.

You just don't set a tile on an angle and start tiling! otherwise, you end up w/what you have. not a good look. Was any of this discussed? did you show him what you want ?

You should just have the entire tile done in the herringbone pattern. you don't have a big enough area to 'showcase' an accent piece. If you tried to do border tile around the herringbone your pattern would be too tiny inside the box.

If you are dead set on a herringbone accent piece, then use 1x2 mosaics, already laid out for you.

Looks like part of the herringbone lines up with the cabinet on the right side but not the left. If so, who ever laid this out has to tear it out and start over. Then you can start with a template as to where the insert goes and then include the boarder.