Is it necessary to leave a gathering for witnessing prayer in the the mosque, despite the hardship that entails?

The answer regarding the ruling on congregational prayer for a group of people outside the mosque during a gathering or ceremony is summarized in the following points:

Firstly: Congregational prayer is an individual obligation (fard ayn) upon adult, capable men, but scholars differ on whether it must be performed in the mosque or if the obligation is fulfilled by performing it anywhere. The majority of scholars hold that performing it in the mosque is a Sunnah and that performing it congregationally anywhere suffices, while others maintain the obligation of performing it in the mosque.

Secondly: There are many excuses that permit missing congregational prayer in the mosque, such as heavy rain, illness, fear, and anything that causes severe hardship is an excuse.

Thirdly: Regarding meetings and conferences, if going to the mosque is easy and without inconvenience, then that is the obligation. However, if that is not possible due to hardship, or inconvenience in the dispersal of attendees, or disruption of the meeting's order, or if there is a benefit in its continuation, then they are permitted to pray in congregation in their location. This concession is strengthened by the jurisprudential difference of opinion regarding the necessity of performing congregational prayer in the mosque, and that the mentioned excuses indicate permissibility in cases of need, especially if the prayer will be performed congregationally and not individually. Some scholars have issued fatwas permitting this for a recognized benefit, such as preserving a study circle or continuing vital work. It is recommended for those organizing these gatherings to arrange them in a way that allows for prayer in the mosque.