What if Denahi killed Kenai?

The majority of us have seen “Brother Bear” so we know that if someone kills an animal in anger and vengeance, they become that animal. My question is what if Denahi never knew that Kenai was transformed into a bear and was successful in killing him since he thought that another bear killed Kenai? Would Denahi also become a bear? Would he be physically transformed into Kenai’s human form? Or would the spirits punish him by making him live with his guilt for the rest of eternity?