The reliable establishment of a report and the definitive establishment of one interpretation of its words are separate questions. A report may be sound while its wording still raises polysemy, lack of specification, or a contextual issue requiring careful interpretation.
A defective argument says: “This report is reliable; therefore anyone disputing my chosen interpretation rejects the report.” That conflates transmission with meaning. A plausible competing interpretation supported by language or other proof must be evaluated on its merits.
Conversely, a clear meaning in a weakly established report is not automatically authoritative. Explicitly distinguish the strength of the evidence from the strength of its indication to locate the real point of juristic disagreement.