• Bidʿah in this discussion concerns a defect relating to the narrator’s beliefs.
• Bidʿah mukaffirah is a belief entailing disbelief; its holder’s report is not a valid proof.
• Bidʿah mufassiqah is a belief or practice entailing sinfulness and deviation; acceptance is stated with two conditions.
• The narrator does not invite others to it.
• The report neither establishes nor strengthens it.
Meeting one condition does not mean that both have been met.