How did the witness of Yusuf testify when he did not witness the events?

Verses (25-28) from Surat Yusuf narrate the story of Yusuf and the wife of Al-Aziz when they raced to the door and she tore his shirt from behind. The woman then said to her husband: ﴿What is the recompense for one who intended evil for your wife but that he be imprisoned or receive a painful punishment?﴾ Yusuf defended himself, saying: ﴿She sought to seduce me.﴾

A witness from her family testified: if Yusuf's shirt was torn from the front, then the woman spoke the truth and he was among the liars; but if his shirt was torn from behind, then the woman lied and he was among the truthful. When Al-Aziz saw that Yusuf's shirt was torn from behind, he said to his wife: ﴿Indeed, it is of your cunning, for your cunning is great.﴾ And he said to Yusuf: ﴿Yusuf, ignore this.﴾ And he said to his wife: ﴿And ask forgiveness for your sin. Indeed, you were among the sinful.﴾

Scholars differed regarding the identity of the witness. Some said he was a child who spoke in the cradle, while others said he was an adult man, or the woman's cousin. It was also said he was not human. As for calling his statement a testimony, if he was a child, it was a miracle for Yusuf. If he was an adult, it was not a testimony in the conventional sense, but rather a judgment based on circumstantial evidence and the indication of the situation, or he guided them to the circumstantial evidence by which they could determine the truthfulness of either party.