Making up for one Sujud missed in the second Rak`ah of the Fajr Prayer by offering one more Rak`ah

Q 2: While I was performing Fajr (Dawn) Prayer with the congregation, the Imam (the one who leads congregational Prayer) - out of forgetfulness - performed only one Sujud (Prostration) for the second Rak`ah (unit of Prayer) and made Tashahhud (a recitation in the sitting position in the second/ last unit of Prayer) and Taslim (salutation of peace ending the Prayer). When Ma'mums (those being led by an Imam in Prayer) told the concerned Imam that he missed one Sujud, he stood up making Takbir (saying: "Allahu Akbar [Allah is the Greatest]") to redo the second Rak`ah. Nevertheless, I thought that the Imam would redo the entire Salah (Prayer) and intended so by my Takbir. The Imam performed the second Rak`ah again then made Taslim and I did the same following him. What is the ruling on this? (Part No. 6; Page No. 38

A: If a person forgets to perform the last Sujud before making Taslim and remembers or is reminded of it; they have to offer such Sujud then Tashahhud then Sujud-ul-Sahw (Prostration of Forgetfulness). They do not have to redo the entire Rak`ah. Accordingly, what the Imam did in the question was wrong and an addition to Salah. However, the Imam is excused for being ignorant of the concerned ruling. Moreover, your intention of redoing the Salah for thinking that the Imam intended so does not affect its validity.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.