What is the authenticity of the claim that the fingerprints of the Messenger of Allah are on a stone in Egypt

This is a letter we received from the sender (may Allah have mercy on him), an Egyptian national residing in al-Khobar. He also writes in his letter: In our city, there is a cemetery inside a mosque, called the shrine of Sayyid al-Badawi. In the same cemetery, there is a stone engraved with five fingers, and everyone knows that these are the fingers of the Messenger of Allah (peace and blessings be upon him). In another city, there is a stone engraved with the fingers of a foot. Is this a fact or a myth? I used to kiss and rub myself against this stone, as people did in our place. Praise be to Allah, I have repented to Allah from this, and I hope that Allah will accept my repentance. But I want to know if these are truly the hand or foot of the Messenger of Allah. Please inform us, may Allah reward you.
Answer: All of this has no basis. They are not the fingers of the Prophet (peace and blessings be upon him), nor are they the fingers of his foot. All of this is invalid. The Messenger of Allah (peace and blessings be upon him) did not come to Egypt and did not visit it. His fingers were not found on any stone to be transferred there. All of this is falsehood and lies. Therefore, it is not permissible to rub oneself against them or seek blessing from them; rather, it is obligatory to remove them.
Likewise, mosques are not to be built on graves. It is not permissible to build a mosque on a grave, nor is it permissible to circumambulate graves, nor to supplicate to their occupants instead of Allah, nor to rub oneself against their graves or circumambulate them, nor to make vows to their occupants, as is done at al-Badawi or elsewhere. All of this is a great abomination. The Prophet (peace and blessings be upon him) condemned the building of mosques on graves and said: He also said (peace and blessings be upon him): When some of the female Companions mentioned to him a church they had seen in Abyssinia, with the images in it, he said: He informed them that those who build mosques on graves and place images on them are the worst of creation, for they are callers to the Fire, we seek refuge in Allah, callers to shirk (associating partners with Allah). One must beware of these calamities, these religious innovations, and these evils introduced by the ignorant. Mosques should be kept separate from graves, and graves should be kept separate from mosques. It is an abomination to build a mosque on a grave or to bury someone in a mosque. It is not permissible to bury people in mosques. Cemeteries should be independent, and mosques should be independent. A mosque is not to be built on a grave, even if it is the grave of a prophet; no mosque is to be built on it.
As for the grave of the Prophet (peace and blessings be upon him) in al-Madinah, he was buried in his house (peace and blessings be upon him), not in the mosque. He, along with his two companions Abu Bakr and 'Umar, was buried in the house, in the house of 'A'ishah (may Allah be pleased with her). Then Abu Bakr was buried with him, and then 'Umar was buried with him. However, when al-Walid ibn 'Abd al-Malik expanded the mosque at the end of the first century, he included the chamber in the mosque as an exercise of independent legal reasoning (ijtihad). He was mistaken in this. If he had left it as it was, it would have been safer and further from doubt. People were misled by this and thought that building mosques on graves was a desirable thing, which is a mistake. The Messenger of Allah (peace and blessings be upon him) was in his house, not in the mosque. He was buried in his house, the house of 'A'ishah. Likewise, his two companions were buried with him in the house, and then the entire chamber was incorporated into the mosque.
Therefore, no person of sound mind should be misled by this. The Messenger of Allah (peace and blessings be upon him) warned against this, repeating it again and again. One must beware of what the Prophet (peace and blessings be upon him) forbade, and no one should be buried in a mosque, nor should a mosque be established on a grave. This is because the Messenger of Allah (peace and blessings be upon him) cursed those who do so, so one must beware. It is also a means to shirk (associating partners with Allah). Yes. We ask Allah for well-being.
The presenter: May Allah reward you.