SharePoint 2016 (Farm 2) had it's own workflow manager server installed, and was running 2016 workflows fine. We have a new (separate) workflow manager server connected to another farm (Farm 1), that is also running 2016 workflows fine. (For a while now).
I want to share this workflow server with the Farm 2 Server, and allow both 1 and 2 to take advantage of a centralized WF Server.
I uninstalled the built-in WF Manager on Farm 2, and re-registered the Farm (WebApp) to the Centralized WF Manager Server. (I set new scope name, gave SPAdmin correct permissions on remote WFM Server).
I can confirm that the Workflow Service shows "Connected" in Central Admin, and that the Workflow Service Application Proxy now shows the remote WF Server.
2013 workflows run on Farm 1, but not Farm 2 now that I have associated it with WFM Server. Not sure what else to try.