What is the ruling on praying behind an Imam who prays Witr with two Tashahhuds during Tarawih, and is it permissible to complete the prayer with him, or is it better to pray Witr at home?

The scholarly disagreement regarding the form of Witr prayer is well-known. The Hanafī school of thought holds that it is not permissible to perform Witr with a single isolated rak'ah; rather, it should be performed with three rak'ahs, sitting between them. One way to perform Witr with three rak'ahs is to connect the three rak'ahs by sitting for the tashahhud after the second rak'ah without performing the salām, then standing for the third rak'ah and performing the salām thereafter. This form is the one designated by the Hanafīs.

The follower (ma'mūm) should follow his imam to attain the reward of praying a complete night, and so that it does not become a source of discord and contention, for disagreement is evil. It is permissible for a Muslim to abandon what is superior for the sake of uniting hearts and gathering the word, out of fear of alienation, as the Prophet, peace and blessings be upon him, did when he refrained from rebuilding the Kaaba on the foundations of Abraham, and as Ibn Mas'ud did when he completed the prayer behind Uthman and said: "Disagreement is evil."