Seems Remedy has a REST API... Has anyone tried it? Any other suggestions?
The out of the box plugin list can be found here Plug-ins - CA Continuous Delivery Director - Integrations - CA Technologies Documentation
As you can see, Remedy is not listed. You can do two things, create an Idea here so the development team can work on that if is something that the community needs, or (and?) create a custom plugin. You can find more about this here Develop Custom Plug-ins - CA Continuous Delivery Director - Integrations - CA Technologies Documentation
Currently, there is no Out of box integration of CDD with BMC Remedy – this will require to develop a new plugin. Customers can develop their own plugins - a guide for the custom plugin can be found at https://docops.ca.com/ca-continuous-delivery-director/integrations/en/develop-custom-plug-ins/sample-plug-in
In case if there is any specific requirement where you need this plugin to be built as part of product features, I will request to raise an Idea on community and interact with PM for same.