«البينة على المدعي واليمين على من أنكر»
The claimant bears the proof; the one denying the claim bears the oath.
The discussion compares this evidentiary principle with a narration about adjudication using one witness and an oath. Does the latter qualify the usual arrangement or depart from it? That question requires a legal analysis.
Testimony in court and a Prophetic report are not the same kind of evidence. One establishes facts in a particular case; the other conveys a general legal norm. Counting “one witness” and “one narrator” does not resolve their legal relationship.