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(2:35) But Satan
> caused them to slip out of it and removed them from that [condition]
> in which they had been. And We said, Go down, [all of you], as
> enemies to one another, and you will have upon the >earth a place of
> settlement and provision for a time(2:36) Then Adam received from his
> Lord [some] words, and He accepted his repentance. Indeed, it is He
> who is the Accepting of repentance, the Merciful (2:37) We said, "Go
> down from it, all of you. And when guidance comes to you from Me,
> whoever follows My guidance - there will be no fear concerning them,
> nor will they grieve(2:38)

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.