Minor Miner changelings can't enter horror form

[MrMagolor]

Sometimes, miners start as dwarves. They are also sometimes changelings. If both of these events coincidence, the miner-dwarf-changeling cannot enter horror form for whatever reason, as "You cannot transform in this form."

I imagine it has to do with it being unable to cast in Lesser Form, but instead of checking for specifically monkey, it checks for any bodytype that isn't human?