vRO 7.3 Multi Node - cannot query workflows

I'm trying to use the vRA 7.3 embedded vRO instance as the master and a stand-alone vRO 7.3 as a slave.

The binding is done with a user account that has admin rights on the remote instance, the session is shared.

Adding the server works fine, however I cannot query the remote workflows and in consequence, cannot create proxy workflows. Querying the remote vRO plugins works, I can search for VMs, query the NSX plugin etc, just querying the vRO inventory for workflows, actions and other objects is not producing results:

Am I doing something wrong here or should I open a SR?