Thank you for posting those links. Looks like the patch may have belong to my grandfather, W.A. "Bil" Goad from Mangum OK. We aren't sure why his brother in law's family had the patchess and jacket. Bill may have taken a trunk of items out to a friend's farm for safe keeping. The friend's son was also Bill's brother in law. He's still living and not sure why they had the items.
Do have one questions? What duties did an engineman do? Is that a mechanic?