So, the ServiceStack FallbackRoute in my code is [FallbackRoute("/{Path*}/")], which is the setup that the ServiceStack documentation says will handle every unmatched route.
If given a route like example.com/api then it will trigger the fallback response correctly.
However if given example.com/api/ then it just returns an empty 200 OK response.
It does handle unmatched routes with content after the slash correctly, so example.com/api/arglkjadkf will be sent to the fallback
I want Servicestack to be able to take the url with the trailing slash after the base path and have it hit the fallback route.