Jen ~
No need to apologize. There is a site (https://www.bakingit.com/) that makes calculators for both the web and mobile devices. They have an awesome app called Cake Slicer that lets you email a PDF cutting chart of size piece you calculated it will feed. This way if they ever say it did not feed what you quoted you have backup. You can’t control how they actually cut the cake but you can provide to them the chart to show how you expected the cake to be cut. Just a thought.
