Most of the Dometic/A&E awnings are actually made by a company called Fiamma and just rebranded by Dometic. In the past I needed a part for my door awning, Dometic said "nope" and Fiamma sent me the part in a week.
Contacting Fiamma is a bit tricky as they mostly are an OEM manufacturer and don't have much of a store front online. Their website is
https://www.fiammausa.com/ and to get parts the best way is to send an email to
parts@fiammausa.com describing exactly what you need. In the past they were very responsive.... sent me a diagram, part #s and pricing.