I'm not sure about doing this through the vRO Infoblox plugin, but I am performing several functions through vRO to manipulate various entries in Infoblox. I had made Infoblox an API endpoint and grab the necessary inputs needed before passing through API calls.
A great set of examples you can use can be found here:
The definitive list of REST examples - Infoblox Experts Community
Hopefully this helps a bit, or gets you moving in the direction you wish to go.