What is the ruling regarding a man declaring one of his two slaves as 'Mudarabbir' (to be freed upon his death) and then declaring the other one 'Mudarabbir' contingent upon the one-third limit exceeding the value of the first slave?

Primary text

If a man declares one slave to be Mudarabbir, and then declares the second slave to be Mudarabbir contingent upon an excess in the one-third limit above the value of the first, and subsequently the first declaration of tadbir is nullified due to revocation, a legitimate claim, or other reasons, the situation is treated similarly to the preceding case concerning specific bequests and the application of the one-third limit.