He changed the name? It used to be called "Meet Me in the Cloud." I like that name better.
Pressing tab or shift-tab will indeed navigate to the avrious Zoom controls.
I don't know what screen reader you are using but if it's JAWS you should know that JAWS 2020 contains some additional Zoom scripts from Brian Hartgen which should become active once you've opened Zoom. Pressing insert-H will bring up a list of some additional hotkeys which he has added. For around $45 you can purchase his Zoom Professional scripts which adds even more functionality. If you're a JAWS user and are planning to use Zoom on a regular basis you may find that his scripts are worth purchasing. The above link will give you more information as to what you'll receive with both the free as well as the pro versions of his scripts.
Jonathan Mosen has also written a book titled Meet Me Accessibly, which is a guide on using Zoom.
Here is a list of Zoom hotkeys. Zoom also allows you to change these default hotkeys to keys of your choosing. You can also assign a hotkey as a global keystroke, meaning that it will work even when you're not in the Zoom window. As an example, alt-A is the default hotkey to mute or unmute your microphone. You might want to make this a global keystroke, meaning that you can use this key from any other program window to perform this function.