I cannot subscribe to dictionary changes in Explorer if I have only Collaboration Hub license. There is no feed. I have the read and write access to it.
That is a known bug. Our developers are already informed. If you are also affected by this or want to check the status of the bug ticket CS-2927, please write to support.
KBA , BPI-SIG-PM-EXP-FEE , Feed for SAP Signavio Process Manager , Known Error