The error was in my total lack of type converters. I had not used them because I thought that as long as all the parameters of a class didn't need type converters the class itself didn't need one. The type converters in MikeT's anwser seem to work.

MikeT's anwser(s) were really helpful though, because they revealed other issues with my code that I did not know of because of my lack of understanding.