Delayed symptoms from the twig damage due to last year's cicadas is a possibility, but unfortunately we can't arrive at a specific diagnosis from the symptoms we can see in the photos. We suggest you have a certified arborist assess the tree. Some arborist companies have their own diagnostic lab where they can test samples for pathogens (or they can send samples to another lab for testing) if an infection is suspected, though not all infections are serious or would require treatment. We don't keep track of specific arborist businesses or individuals, nor do we recommend particular companies, but you can use the link above to search for licensed arborists. Some are employed by tree-care companies and others work independently as consultants.

Miri