Is congregational prayer with a colleague at work valid, and is it better to pray it congregationally on time, or to go to the mosque after work?

Congregational prayer is obligatory for a Muslim man who is able to perform it, unless there is a valid excuse. However, it is not a condition for the validity of the prayer. If a Muslim is unable to go to the mosque, it is better for him to pray in congregation with a companion at the beginning of the prayer's time, in order to attain the virtue of congregational prayer and praying on time, and to avoid delaying the prayer beyond its prescribed time, which is impermissible. Some scholars consider it disliked to establish a second congregation after the prayer of the regular Imam.