When a new custom resource is added for a Cloud Elements element, there are several steps to be checked before expecting the new resource to be available for VDR mapping:
1. Assure the correct mapping for the custom resource so that metadata can be retrieved from the provider REST API. You can find all steps to be followed when defining a new resource here.
2. Add a request model for the custom resource; if the custom resource has also a POST call then the response model is also needed. The model can be created manually or through the option Generate from sample payload. If the request model will be added and saved, then the resources will be available for VDR mappings and also will be displayed in the GET/objects call.
3. After these changes are applied, hard refresh the browser page several times and then the resources will be available for mapping them using a VDR.