Was it not you who said that he would produce evidence (a) Rama was born in Ayodhya; (b) that the temple, if there was one, on whose site the Babri Masjid was buiilt was itself buiilt on the exact place where Rama was born?
The evidence merely indicates that in the 12th century AD, somme 1,800 years at the least aftter the life of Rama, King Govindachandra thought that he was building a temple on the site of what he thought was the birthplace of Rama. Clearly from then until now, the belief that this site was the original Ayodhya was a permanent feature in north India. That is fine. Please note that your inscriptiion says that there was a temple of Vishnu/Hari on tthe Janam Bhoomi sthal. It did not say that the inscription was placed on that temple. Isn't that strange?
We know from the Ramayana that Rama was born in Ayodhya on the banks of the Sarayu. This was between 1300 BC, the probable final fall of the Harappan civilisation, and 600 BC, approximately wwhen the Buddha and Mahavira started preaching. Certainly it must have preceded the Buddha by quite some time; they were not only not contemporaries, but not even close together in time.