We have reviewed inquiry no.1851 for the year 2003, which arrived through the Internet, and includes the following:

We entered a mosque as a group and we found that the imam was in the second tashahhud (i.e. the last position in the last rak'at of the prayer). Can we join him at that point in the prayer, or do we perform a separate prayer, as some of us said that the prayer cannot be achieved without praying a complete rak‘at [with the imam].

 

The majority of scholars agree that one achieves the congregational prayer when one participates with the imam in any part of it at any point, even if it is the end of the second tashahhud before the final closing salutation (salam).

Based on this principle and the circumstances stated in the question:

It is permissible for you to join the imam in the last tashahhud and, according to the majority of scholars, you will have the reward of the congregational prayer.

And God the Almighty knows best .