His work hours conflict with Taraweeh prayers – what should he do?

Pray whatever you can of taraaweeh in congregation with the imam. It does not matter if you leave for work after two or four or six rak’ahs, etc. Then complete the prayer at home and pray witr at the end. 

If you find a mosque that prays early and you can complete the prayer with them and then go to work, this is better, because the Prophet (peace and blessings of Allah be upon him) said: “Whoever prays qiyaam with the imam until he finishes, it will be written that he spent the whole night in prayer.” Narrated by al-Tirmidhi, 806; classed as saheeh by al-Albani in Saheeh al-Tirmidhi. 

And Allah knows best.