I'm glad you got it to work and I must have missed that post that you got it to work.
"I forgot the beginning quote and it was not recognized. I then put in the quote, pressed Enter and the "update", or in this case "reversion", downloaded and installed."
For future reference you don't have to use quotes in commands any more. You can still use them, but they must be matched with closing quotes. That article is older and when it was written quotes were needed. Forget about quotes and avoid hassles like non matching quotes.
"To revert back to any other build, you can find the build numbers here:
Version numbers of update branches for Office 365 clients."
Yes, but one can get confused about which version to use. It is best to look at the Update history in your Outlook application which shows the exact build number for your Outlook. Outlook Update History = File > Office Account, click dropdown for Update Options and select View Updates. This goes directly to the Microsoft Updates page for this specific Outlook application. This differs slightly from those instructions that you posted and its the way I chose to perform this action.
BTW: Microsoft released a second version of 2306 on July 11, 2023, but appears to affect only Excel and Word app. Hopefully Microsoft will fix this bug soon.