Okay. Thanks for the response and reproduction steps. I was able to reproduce that issue very easily. It was something that we had not tried as we had all play tested several iterations. It also only required two changes. I know that I cannot upload a new version to the jam, but if anyone wants to play it the way that it was intended, it can be found here.
It is a terrible issue as it will ALWAYS cause an integer overflow once you take a castle and add the levy of the castle to the now garrison maximum integer value and will wrap around making it impossible for you to defend the castle as Noyemi quickly discovered. Thanks for that!