I’m getting an error that says "BlueSky Timer cannot currently join a meeting where authentication is required."
You will need to disable "Require authentication to join" or "Only authenticated users can join: Sign in to Zoom." The BlueSky Timer does not have the capability to enter information to get past this authentication step.
If you need a security feature, you can enable passcodes and/or use a waiting room. You'll then just need to make sure the passcode is embedded into the invite link and/or need to admit the Timer in from the waiting room.
You can also update this setting for all future meetings by logging into the Zoom website and going to Settings, then Security. After updating your meeting settings, re-invite the Timer.