Which version of PowerBI Report server are you publishing to? Tables and Matices are only available in the current August preview. Also which versoin of PBI Desktop are you using?
Iam using SQL server 2016 with SSRS and i integrate power bi report server on it ,, Also i have two portals one for SSRS and the other one for power bi report server. The version of power bi report server 1.0.6398.10090 and the version of PBI desktop iam using september update .