Imperfectly cut tile (4mm short) within acceptable range of error?
Nobody else will ever notice it. You'll forget about it in a week, unless you let it drive you insane, which will result in everybody feeling bad, since the tile guy is unlikely to see one corner of the range hood being 2mm offset from the opposite one as remotely within the realm of a sensible customer complaint.

If this will drive you mad, I recommend that you hire a different person to redo that part of the work and explain to this other person exactly what your expectations are. One of those expectations should be pay a lot for this service.

Personally, I would just make the grout line a bit thicker on that side or put some colored caulk in there or something. It's a tiny tiny difference that nobody is ever going to notice.