That resurrection will occur is established by revelation. The manner in which it occurs is a further question: will separated bodily components be gathered, or will a body that ceased to exist be restored numerically as the same body?
Historical disagreement over such descriptions must not be confused with denial of resurrection itself. Rejection of the event and competing rational accounts of its mechanism are different matters.
The reasoning therefore proceeds in order: divine power and explicit revelation, the continuity of the individual person, and then objections to particular models of restoration.