InitiateFileTransferFromGuest + download results in java.net.noroutetohostexception (vSphere 6.0 and vRO 7.3)

I have a vRO workflow that attempts to download a log file from a guest operating system using InitiateFileTransferFromGuest + download. Guest operations such as launching a script on the target guest OS completing successfully plus the fact that this is a new vSphere environment behind a firewall lead me to believe that the problem is a blocked port between vRO 7.3 and the ESXi 6.0 host(s). The problem is that the documentation doesn't make explicitly clear which port needs to be open for this.

Do I need to open tcp/443 (Client connections) or tcp/902 (NFC) or some other port(s)?

Port requirements for ESX/ESXi (2039095)

https://kb.vmware.com/kb/2039095

Incoming and Outgoing Firewall Ports for ESXi Hosts

https://docs.vmware.com/en/VMware-vSphere/6.0/com.vmware.vsphere.security.doc/GUID-171B99EA-15B3-4CC5-8B9A-577D8336FAA0.html

Managed Object - GuestFileManager(vim.vm.guest.FileManager)#InitiateFileTransferFromGuest(initiateFileTransferFromGuest)

https://vdc-repo.vmware.com/vmwb-repository/dcr-public/723e7f8b-4f21-448b-a830-5f22fd931b01/5a8257bd-7f41-4423-9a73-03307535bd42/doc/vim.vm.guest.FileManager.html#initiateFileTransferFromGuest