I've heard the screaming ouija board story before! Told by an Elder's wife. Wonder if it was about your sister or if all ouija boards scream when burned in JW folklore.
My mom's best burning was when she decided to burn all the painings my father had given my brother and I. He was a very prolific and talented artist. It was general knowledge at my hall that my father was demonized as he was a big scary looking biker sort and many of his paintings were of a surrealist style. He even did the occasional flaming skeleton on bike to sell at rallys which JW mom was most fearful of. Anyway when she pitched the paintings into the barrel stove she couldn't fit one all the way in the stove, it flamed up, almost burned the house down, and singed her arms in the process. She declared this proof 'o demons as they had tried to take her with them! My dad gave us more art when he found out & told my mother under no circumstances would she burn these ones or he'd go to the social worker.