لَا رَيْبَ فِيهِ
There is no doubt in it. (al-Baqarah 2:2)
A denier may be treated rhetorically as a non-denier when compelling evidence is already available: careful consideration should remove the grounds for rejection.
This does not claim that the person has actually ceased denying. It means that the denial is treated as unworthy of additional linguistic concession. An apparently unreinforced report can itself signal that the matter should be evident.