Regarding the time share deed listing two individuals with right of survivorship. Are you saying that by him getting a power of attorney listing the property to his son would void a survivorship deed and I would own the property with his son?

No, he cannot take his joint tenant's interest without that person's consent. Real property, including a time share interest, is normally conveyed by deed. If he has a power of attorney from the joint tenant, that POA may howerver authorize him to convey the other person's interest to the son.