I have not seen any reports of someone being able to query the solar inverter for production data beyond the startup period. I also have a similar setup, Powerwalls and multiple existing PV system including one with Tesla Solar Inverter. I couldn't get Tesla to provide me separate production data for the PV system with the inverter. It appears that the system is calling home and sending data (based on the network traffic that I see) so I believe the data is there but Tesla currently doesn't make it available.
I ended up adding my own monitoring on it so I can see the production separately from the total of all the PV systems. My older Solar City system is available a separate product in my app and it is also part of the total PV that I get from Powerwall. I had my own monitor for my previous system as well. I could have done arithmetic to compute the production of the new Tesla Solar inverter system but I chose to add another monitor for it (IoTaWatt).
Recently Tesla added a "revenue grade" Neurio for the system with the Tesla Solar inverter to correctly calculate the renewable energy credits. So there are now a minimum of 4 things monitoring the output of that PV system, the inverter itself, the Powerwall, my IoTaWatt, and the revenue grade Neurio.