To answer the question on the randomizer.....you can load any OBJ mesh into the Octane scene in place of a Revit object. For example, you can assign a Revit RPC person with an OBJ person mesh. For Revit elements which are assigned OBJ proxies like this, you can load a transform CSV file (as you would with Octane Standalone) to "instance" that OBJ mesh many times. If the "randomizer" plugin can write the instance transform to CSV, you could load that into the plugin.
When you load OBJ proxies, you can also edit that Octane materials for those proxies, so the whole system is very easy to use.