Is it true, as has been mentioned, that Allah will question Jibreel, the Prophet, and the Companions about the trustworthiness of the Qur’an, and the Companions will bear witness to its delivery from their graves, and then we will be questioned about it?

There is no origin for the mentioned statement in the books of Hadith or otherwise. Attributing it to the Messenger of Allah, peace and blessings be upon him, is a lie and a major sin. Jibreel, the Messenger, and the Companions all fulfilled the trust completely, which is the message of Islam. Allah named Jibreel "the trustworthy" in His saying: (The Trustworthy Spirit has brought it down). And the Prophet, peace and blessings be upon him, said: (Do you not trust me, though I am the trustworthy one of Him who is in the heaven?). He also said: (I have left among you that which, if you hold fast to it, you will never go astray after it: the Book of Allah). The Ummah affirmed his delivery, performance, and sincerity. He said: (There is nothing that brings one closer to Paradise and distances one from Hellfire, except that it has been made clear to you). And the Companions conveyed the religion to the people and left nothing out. The Ummah bears witness to the conveyance of the Prophets, as in His saying: (And thus we have made you a justly balanced community that you will be witnesses over the people and the Messenger will be a witness over you).