Does the prohibition of cleaning oneself with bones and dung because they are the food of the jinn mean that jinn will cause possession or harm to humans? And does throwing dirty children's diapers into containers with bones lead to harm from the jinn?

The prohibition of cleaning oneself with bones and dung is for the purpose of حرمة (prohibition/sanctity), because they are the food of the Jinn and their animals. Moreover, cleaning oneself with them may expose a person to harm from the Jinn. Disposing of soiled diapers with bones in the trash might fall under the prohibition of spoiling the Jinn’s food. Many scholars have forbidden the slaughtering of animals with any bone, because it spoils the Jinn’s food by defiling it with blood, and this action should be avoided.