You have not answered the question. Who was Shad'dad, the man who claimed to have made a paradise on earth named 'erum'? Is this a true story or is it a fabrication?

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger. 

It is mentioned in the books of Tafseer (Quran interpretation) and history that Shaddaad ibn ʻAad was the one who built the city of Iram.

Al-Baydhaawi wrote:

“It is said that King ʻAad had two sons, Shadeed and Shaddaad. After the death of ʻAad, they succeeded him and gained such power that the east and the west yielded to them. Shadeed died first, and Shaddaad became the foremost ruler of the world. He heard the description of Paradise, the inlaid rubies and pearls and other bounties; so he constructed a paradise in the desert of ʻAden to resemble the Paradise of Allaah and called it Iram. When the construction process ended, he set out towards it with his people. When he was only at a distance of a day and night from it, Allaah sent a Sayhah (scream or violent sound) from the heavens that destroyed them all, and neither Shaddaad nor any of his company set eyes on the city.”

You see that this story is just a tale that is told, and its authenticity cannot be verified. Do not concern yourself with it since knowing about it is of no benefit and having no knowledge of it is of no harm.

Allaah knows best.