I think it would be both silly and morbidly ironic if the witch casting the spell died because she was embracing him when it went off. I also get the sneaking suspicion that Alice's mom was killed by the duke's curse before they realized there was a problem.
This is the power of mimetic effects. Despite every sign to show that this scp is more than just a smart raccoon, and the indications of it being a specific agent, the mimetic effect forces them to believe that it is just a slightly strange raccoon.