Is it permissible to pray Tarawih with two imams and two witrs in the same prayer, such that the first imam prays 8 rak’ahs and performs witr, then the second imam completes 20 rak’ahs and performs witr, with the worshipers who wish to complete the twenty with the first imam not performing witr?

The preponderant opinion is that two imams in one mosque can complete each other's prayers, and they are considered as a single imam. The worshiper with them does not attain the reward of standing with the imam until he departs, unless he stands with the imam and his deputy (the second imam). It is more preferable for the congregants to pray until the second imam departs and to pray Witr with him. The first imam should complete the prayer with his deputy until he departs. There is no harm if the first imam prays Witr and some people pray Witr with him and then depart, while the remaining people complete the prayer, but those who depart will not attain the promised reward mentioned in the hadith.