Study Bava Batra folio 154B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
R' Yoḥanan explains: Granted, according to my explanation of the Mishnah, that I say that the proof must be presented by bringing witnesses, I can explain the baraita. Since R' Akiva said to the buyers: Bring witnesses, and they did not find witnesses, this is the reason that they came and said to him: What is the halakha? Is it permitted to examine him? But according to you, that you say that the proof is presented by ratification of the deed, why do they need to examine him? Let them ratify their deed and they should be established as owners of the property.
מי סברת נכסי בחזקת בני משפחה קיימי – וקא אתו לקוחות ומערערי? נכסי בחזקת לקוחות קיימי – וקא אתו בני משפחה וקא מערערי!
R' Shimon ben Lakish replies: Do you maintain that the property stood in the possession of the members of his family and the buyers came and contested their possession of the property? Rather, the property stood in the possession of the buyers, and the members of his family came and contested the sale. Since they claimed that the deed was invalid, they could not prove their claim by ratifying the deed, but only by bringing witnesses or examining the body.
הכי נמי מסתברא, מדקאמר להו: אי אתם רשאים לנוולו, ואישתיקו. אי אמרת בשלמא בני משפחה קא מערערי, משום הכי אישתיקו. אלא אי אמרת לקוחות קא מערערי, אמאי שתקי? לימרו ליה: אנן זוזי יהבינן ליה, לינוול ולינוול!
This, too, stands to reason, as R' Akiva said to the claimants: You are not permitted to disgrace him, and they were silent. Granted, if you say that the members of his family were contesting the sale, due to that reason they were silent, as they accepted that they should not disgrace their relative. But if you say that the buyers were contesting the claim of the relatives, why were they silent? They should have said to R' Akiva: We gave him money, and if our right to the property cannot be proven without disgracing him, let him be disgraced.