I doubt this was the case as the verses below indicate that how Adam was forgiven and no mention is made of the black stone in this context:
And We said, "O Adam, dwell, you and your wife, in Paradise and eat therefrom in [ease and] abundance from wherever you will. But do not approach this tree, lest you be among the wrongdoers(2:352:35)
But Satan caused caused them to slip out of it and removed them from that [condition] in[condition] in which they had been. And We said, Go down, [all of you] you], as enemies enemies to one another, and you will have upon the >earthearth a place of settlementplace of settlement and provision for a time(2:362:36)
Then Adam received from his Lord Lord [some] words, and He accepted his repentance repentance. Indeed, it is He who who is the Accepting of repentance, the Merciful Merciful (2:372:37)
We said, "Go down down from it, all of you. And when guidance comes to you from from Me, whoever whoever follows My guidance - there will be no fear concerning concerning them, nor nor will they grieve(2:382:38)
I would advice against reading articles that make statement without baking them up with evidence or how a conclusion is drawn especially when these articles are written by those who are not scholars or known to be knowledgeable in the field.