What is the ruling if the defendant (the alleged manumitter) is insolvent (mu'sir) when one partner claims the other manumitted his share?

Primary text

If the defendant is insolvent, the defendant's assertion, supported by an oath, is accepted, and nothing of the slave is freed. If the claimant is a just witness (adl), the slave swears alongside the witness's testimony, and consequently, half of the slave becomes free.