Is a conditional testamentary statement valid if the condition is met posthumously?

Primary text

If one of these individuals states, 'If I am freed upon my death, then two-thirds to so-and-so is a will,' and they are subsequently freed and then die, their will is valid. This opinion is held by Abu Yusuf, Muhammad, and Abu Thawr, and there is no known disagreement from others regarding this specific conditional bequest.