I am trying the Retrival method provided I use the JDBC connector to connect the Oracle DB. However there is a big limitation when it comes to the REST API consumption from cloudforms. BMC Remedy do not have the ability to consume external REST API.
While it is true that presently CMDB does not have any OOTB support for consuming Cloudforms (or any external REST API for that matter). Nevertheless, you may author Federation adapter and create Federation Datasource for fetching data from CloudForms through their REST interface. Following could be helpful to you for authoring a new federation adapter.
I'll bring it up in R&D forum and hope this gets added to our roadmap, if not there already.