What earlier data does their request for names possibly justify?
Ezra 5:4 (ESV)
4They also asked them this: “What are the names of the men who are building this building?”
Their question regarding the names of the men may have been the reason why we have a long list of names of all the people who came back from the exile in Ezra 2:1–70. That could well be the list that Tattenai was given.
4 They also asked them this: “What are the names of the men who are building this building?”