Is the story that includes the Bedouin's supplication at the grave of the Prophet and Umar's (may Allah be pleased with him) saying, "O Allah, I supplicate to You with what this Bedouin supplicated," authentic?

Umar's mention was not found in this story, and what was found similar to it is attributed to Al-Asma'i, who mentioned that one of the unnamed attendees commented on the Bedouin's words. This story cannot be used as a proof due to the absence of a chain of transmission for it, and because the Bedouin's action is not a proof, and because it does not include supplicating to other than Allah or asking by the right of a created being. Also, the one who said, "O brother of the Arabs, Allah has forgiven you," is unknown, and such tales are a sign of the ignorance of their teller.