Alright.
I can't replicate the defense bug reliably either, but do you need my save?
It just happens randomly every few mins I suppose, with the highest turnout being at the beginning of a fight if i choose defense with maximus. (4 out of 6 times) I accidentially oversaved the one when he was still a level 1 wizard but it did happen with him as a level 6 wizard too.
Not sure if you want me to post my save here though. It has fixed itself after getting the wizard equivalent though. Just tell me how to get my save to you if you need it and i will give it to you.