Is testimony complete when the scope of the granted power of attorney differs regarding the sale of a slave?

Primary text

The testimony is not complete if one witness testifies the principal authorized him to sell his slave independently, and the other testifies the principal authorized him to sell the slave and Zayd, or if the second witness adds a condition such as, 'Do not sell him until you seek my permission or seek the permission of so-and-so.' The first testimony establishes the agent's independent authority to sell without condition, whereas the second testimony negates this independence by adding a limiting condition, rendering the testimonies contradictory.