Is the Tashahhud mentioned in the the question the correct Tashahhud of the prayer, and if not, what is the correct Tashahhud?

Several authentic versions of the Tashahhud and Salutation upon the Prophet (peace be upon him) have been reported from the Prophet (peace be upon him), and scholars have unanimously agreed on the permissibility of all their forms. The mentioned form of Tashahhud is authentic, and its wording is: "All greetings are for Allah, all purifications are for Allah, all good deeds and prayers are for Allah. Peace be upon you, O Prophet, and the mercy of Allah and His blessings. Peace be upon us and upon the righteous servants of Allah. I bear witness that there is no god but Allah, and I bear witness that Muhammad is His servant and His Messenger." The form of Salutation upon the Prophet (peace be upon him) is authentic, and its wording is: "O Allah, bless Muhammad and the family of Muhammad, as You blessed Abraham and the family of Abraham, indeed, You are Praiseworthy and Glorious. O Allah, grant well-being to Muhammad and the family of Muhammad, as You granted well-being to Abraham and the family of Abraham, indeed, You are Praiseworthy and Glorious." As for the addition between the Tashahhud and the Salutation upon the Prophet (peace be upon him), such as: "I bear witness that Your promise is true, and that Your meeting is true, and I bear witness that Paradise is true, and I bear witness that the Hour is coming without a doubt, and that Allah will resurrect those in the graves, indeed, Allah does not break the promise"; its chain of narration is very weak due to the presence of Aban ibn Abi Ayyash, who is considered abandoned in Hadith. Therefore, one should restrict oneself to the Tashahhud and the Salutation upon the Prophet (peace be upon him) and omit the aforementioned addition.