Is it true that one of the prophets saw the words "Lā ʾilāha ʾillā Allah, Muḥammad Rasūl Allah" (There is no god but Allah, Muhammad is the Messenger of Allah) in Paradise before the birth of the Messenger, may Allah bless him and grant him peace?

There is no authentic hadith stating that Adam asked Allah for forgiveness through Muhammad. The hadith narrated by Umar ibn Al-Khattab in Al-Mustadrak, which mentions Adam seeing Muhammad's name on the Throne, is a fabricated hadith. Imams of hadith have denied Al-Hakim's authentication of it. Al-Bayhaqi deemed it weak, and Al-Albani judged it to be fabricated.