It does sound more like EDS Hypermobility issues. No one ever has an issue-until they do. There is so much ongoing R&D with EDS, so he should definitely make sure he has or connects to a true EDS specialist. Gastroparesis is common in these patients, but there are so may autoimmune and other rare diseases that may be the culprit. Has anyone looked into Churg-Strauss or EGPA? The weight loss, abd pain/issues and pain form a seemingly unusual source are all potential signs, though there is no definitive testing, and like all of these conditions, it can be very complicated to get the right diagnosis.