What is the ruling if someone accuses two witnesses of giving false testimony (zūr)?

Primary text

If an individual accuses two witnesses of giving false testimony, the judge must summon them. If the two witnesses admit to the false testimony, they must compensate the claimant. If they deny the accusation, and the claimant provides evidence confirming their admission, then the admission is established against the witnesses, and they must compensate. The witnesses are not to be administered an oath (ihlaf) upon denial, because administering an oath might discourage the fulfillment of testimony and hinder the presentation of valid evidence. This is the position of Al-Shafi'i, and no dissenting opinion on this specific matter is known.