Is it true that there were verse(s) of the Quran dictating the stoning of adulterers?
Yes. Once upon a time there were verse(s) of the Quran dictating the stoning of adulterers.
The verse of Stoning was REVEALED and it was RECITED and it was also MEMORIZED by the sahaba.
“Allah sent Muhammad with the Truth and revealed the Holy Book to him,
and among ...
The Muslim has committed fornication because (s)he is unmarried. The non-Muslim has committed adultery because (s)he is married. Both adultery and fornication are called Zina. Non-Muslim's marriages are considered valid.