As Salam Aleykum tonight we finish the quran and the Imam said that it’s authentic to make congregation dua , they turn the lights off while doing it , this takes around 30 min , do i wait outside for witr or leave ?

Inna lillahi waena ilayhi rajioon our salaf have never done this in taraweeh what is narrated is from anas ibn malik that when he finished the quran he would make dua and gather his family but no mention of dua in congregation.