Bug since the character creation is borked and loads undead as humans/first default result on list instead of caring about the bone tag. Same thing can actually happen to Fane, but its a lot less common since he has his own script that specified him as HumanUndeadMaleHero instead of going Hero and then next default result. Note that it also negatively influences pathing and a few story triggers (why you might path through heals or have blessed water dropped on you) that do not read the tags (like Undead, Red Prince, Noble, Hero, Mystic, Dwarf...), but the character name itself.
Sadly i have no clue how to fix it since around 80% of everything that could be of value for modding past new abilities using base effects/items is hard coded (or files for it are packed in some place that isnt the data folder) while the scripts have 90 layers of pointless padding to go through to do anything and some commands work for one thing yet not the other (e.g. check vs if, putting conditions in brackets vs c1&c2&c3 and so on for seemingly no reason, tho there probably is some convoluted one probably related to the age of the engine or something like that) and trying to figure it out gives more headaches than old school point and clicks without the benefit of being able to just try everything without screwing it up.
