The soil sample results are for the most part within what I would say are a normal range for most of the tests they conducted. Nothing really jumps out as seriously out of the ordinary. The pH is typical, organic matter content is good and though the phosphorus and calcium are high, it's something I've seen in other soil tests and not something I would expect to cause injury to woody plants. Dieback of trees as you describe is unlikely to be the result of any of the soil characteristics in these tests being drastically wrong. It's usually other problems. One problem that can cause issues is soil compaction, which of course is not a test they conduct. But the soil can be of reasonable quality (like yours), but if compacted can be problematic for tree health. Also if the drainage is in any way inadequate, that will cause problems for roots of most landscape trees. Sometimes these two things occur together to create a wet environment. and then of course there can be disease or pes issues as well. Do you have any imagery of the trees in question you can share? Perhaps a photo or two showing the situation could provide some clues.