So… this is awkward. After scouring this forum for clues I found a lot of people having the same problem but they seemed to abandon the discussion before getting to any resolution. It wasn’t until I read this comment from @ActivateDza:
that I finally realized what I was doing wrong.
I’m going to document it here so it can help others in the future.
If you look at the serverless invoke local call above, the function passed in is create but the event.json object passed in is the get-event. So in my haste to test all these new apis I was using the up arrow in the terminal to recall the last command and editing the name of the event object but not the function. Once I fixed that all the tests passed.