In which siege did Yazid participate
To find out whether Yazid is included in the forgiveness given in the Hadith, it should be found in which attack of Constantinople did Yazid participate and in which year?
There are 4 opinions about this.
1) He participated in the battle of Rome in 49 Hijri and he reached Constantinople as given in Bidayah wan Nihayah, Vol. 8, Pg. No. 34:
Translation: In 49 Hijri Yazid bin Mu‘awiyah attacked the kingdom of Rome and reached Constantinople.
2) Yazid participated in the attack of 50 Hijri, as given in ‘Umdatul Qari, Vol. 5, Pg No. 558:
Translation: Muslims reached Constantinople in this attack and laid siege to it and Yazid was the commander on the behalf of his father.
3) Yazid participated in the attack of 52 Hijri Imam Badruddin ‘Aini Hanafi (May Allah shower His mercy on him) preferred this opinion and said that this opinion is to be preferred that Yazid participated in the 52 Hijri attack of Constantinople, as given in ‘Umdatul Qari, Vol. 10, Kitab Ul Jihad, Pg No. 244:
4) Hadhrat Mu‘awiyah (May Allah be well pleased with him) sent Yazid in 55 Hijri to attack Constantinople, as given in Al Isabaa fi Ma’arifatis Sahabah.
Whichever opinion is preferred, it does not prove that Yazid participated in the first siege of Constantinople, because Constantinople had already been attacked multiple times before it.
About the opinions of Yazid’s participation, the first one according to chronological order is 49 Hijri, when before this in 32 Hijri Hadhrat Ameer Mu‘awiyah and after him in 43 Hijri Hadhrat Busr bin Artaah, then in 44 or 46 Hijri, Hadhrat ‘Abdur Rahman bin Khalid bin Walid (May Allah be well pleased with them, had all attacked Constantinople. Neither the books of Hadith nor the books of Hadith criticism mention Yazid’s participation in any of these attacks nor has any historian mentioned it. Therefore, saying that Yazid participated under the Hadhrat ‘Abdur Rahman bin Khalid bin Walid (May Allah be well pleased with them) and is therefore forgiven is not supported by any of the books of Hadith criticism or history. Instead by reconciling the books of Hadith criticism and history, we come to know that this is a fabrication and a blatant lie. Believing in this without any support from the canons of history is akin to changing the history of Islam.