Earlier quoted context omitted.
This. Happens all the time and then people say, "You never showed up." The authuser=1 tip is great. Thanks for sharing that!
At the bottom, in tiny font, there is a "change account" link that gives you the ability to switch that call to a different Google account. It's tiny, you might have missed it...
Google knows which accounts I'm logged in as. They know which accounts have access to the meeting. If I'm logged in as one of these accounts, why not do it automatically for me?