FYI there may be ways for truth to prevail if the claim was a lie.
In a different but related context, I learned from Rav Reuven Weiner of Kollel Iyun Hadaf —
If a person, after admitting, claims he made a mistake and wants to retract his Hoda’ah see Choshen Mishpat 81:23. The Rema and the Shach differ about when the retraction is effective.
A person can put a shibud momunes on himself. One application I heard of a few years ago from Rav Arye Leib Katz, if a person after 120 wants to give to his sons and daughters, he can be meshabed himself a large sum of money to his daughters, which will in turn be a shibud on his nechasim. This way he is not being morish to his daughters bimokom there are sons. Rather, they are getting what really belongs to them through this shibud.