I believe that yes they agreed to what he gets paid in 2020 and, exactly, no arbitration for that.
But his grievance about 2015: being held back at the start of that season so that it did not count toward his MLB contract was a different matter that was still undecided. He won the Rookie of the Year that year and had a compelling albeit long shot case. By losing he is still under control through 2021. Or, he can be traded and the receiving team gets him for 2 years.