Hi Chris Layne,
Have you had a chance to try the steps in the AI Answer yet? If so, how did it go? Please let me know whether Windows Sandbox was removed successfully, remained listed after restarting or displayed an error.
If it is still present, please share the exact error message or code, along with your Windows version and build. You can find this by pressing Windows key + R, typing winver and selecting OK. That information will help narrow down the most suitable next step.