Question Summary:
Should one perform Sajdah-us-Sahw when the imam makes a mistake in reciting the Qur’an?

Question Detail:

 
Today i prayed Maghrib and the Imam did a surah but he forgot it a little.
So a guy next to me said what comes next, Cause the Imam hesitated.
(The Imam wasn't the usual Imam)
But the Imam did Sajdat al-sahw. But my question is, is that right or do
you have to do something else if someone makes a mistake or hesitated.

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
The responsibility of an Imam cannot be held by just any one. There are many injunctions one need to know prior to becoming an Imam. Just as a surgeon cannot operate without knowing how to operate before operation, and a person cannot lead Salah without knowing the basic rules of Salah. 
It is not Wajib for the Imam to perform Sajda-us-Sahw when he makes a mistake in Qira’at (reciting the Qur’an) [1][2][3].
And Allah Ta’āla Knows Best
Immad Bin Arshad
Student Darul Iftaa
California, USA
Checked and Approved by,
Mufti Ebrahim Desai.
www.daruliftaa.net