What is the proper testimony required when a witness observes a mortgage transaction involving an increase in secured debt?

Primary text

If two witnesses perceive a transaction where an item is mortgaged for two rights, and they believe the transaction is void (*fasid*), they are not permitted to testify to its validity. If they believe the transaction is valid, they must not testify broadly that it was mortgaged for both rights, but rather they must testify precisely to the manner in which the transaction occurred so the judge (*hakim*) may exercise his legal discretion.