Should the worshiper prostrate for forgetfulness (sujud al-sahw) if he made a mistake, then completed the missed rak'ahs, and is there prostration if the mistake was in wording, such as repeating verses or other similar errors?

There is no prostration (of forgetfulness) incumbent upon the congregant (ma'mum) if they make a mistake, because the Imam bears responsibility for their forgetfulness as long as it occurs within the main body of the prayer. However, if the congregant joined the prayer late (masbuq) and stands up to complete their prayer after the Imam has given the salutation, then their forgetfulness is their own responsibility and their Imam does not bear it for them. Also, there is no prostration (of forgetfulness) if the mistake was merely repeating a verse or a remembrance (dhikr).