I have been following this guide - https://collab365.community/configuring-sharepoint-2013-to-support-workflow-management/
To enable SP2013 workflows within SP Designer. (within my SP2016 farm)
I ran Get-WFfarm to confirm I'm using the correct WorkflowHostUri.
I have checked my bindings in IIS and all looks as though it should do.
When I try to view the XML in browser, I get - "An internal error occurred" there as well.
Troubleshooting guides appear to be few and far between online, but those I have found, I have tried.
Has anyone else had the same issue? Or does anyone have any suggestions on how to resolve?