Still Mystery
First of all, Kate believed that she kept the artifact in one drawer. But it wasn’t there. She checked the whole house and she didn’t find it. It looks like it was stolen. She alerted the police officers and they came. It didn’t look like anyone broke into the house.
It looked more like Kate hid the artifact and she didn’t want to give it to the police officers. But there is no evidence for this either. It is a mystery in the lack of a better word. Nobody knew the truth. But there is one theory.