Is it permissible to wait for the Imam to finish the two taslims in order to join a second congregation, if one missed the bowing of the last raka'ah in the first congregation?

Scholars differed regarding attaining the virtue of congregational prayer for one who catches less than a unit (rak'ah) of it. The well-known opinion among the Shafi'is and Hanbalis is that one attains it as long as the Imam has not said the taslim, basing their view on the generality of the Prophet's (peace be upon him) saying: "So whatever you catch, pray, and whatever you miss, complete." Some scholars believe that waiting for another congregation and joining it is more preferable, because attaining its virtue is certain, and because catching the prayer from its beginning is better.