Teams MTR firewall requirements for Zoom WebinAr meetings

[Audiss]

Our Firewall guys use the Zoom published dynamic lists for Zoom meetings. 

List 1: https://assets.zoom.us/docs/ipranges/ZoomMeetings.txt

List 2: https://assets.zoom.us/docs/ipranges/ZoomCDN.txt

Our Teams MTR's can connect just fine to normal Zoom meetings but are unable to connect to Zoom WebinAr meeting types. 

The meeting screen shows briefly then the call disconnects.   I am hoping to track down what potential additional ports and addresses may be required for WebinAr meetings.

We first made changes to the "real time data center location" country selection.  Since when we first started attempting to monitor what was being blocked we had connections attempting to hit hong kong ip space.

I had our business partner test and remove all data centers except for US and Canada and that did not help our test connections.

Has anyone else seen or had these issues with connecting to webinars?

Our units are Crestron Teams MTR's.  Thanks much