Likely - not all 610k documents are authored by those 59 people.

59 people are interesting to look at. 610k documents are related to the investigation probably by search/graph.

Realistically, not all 610k are read manually.

Also, the interactions span over 15 years.

I have 24k emails over the last year in my work email. I think this is fairly typical in large companies.

In a University it is completely out of control. Every individual you ever meet or encounter electronically seems to generate an email or meeting invite from them, their university, their department, their school/faculty and from associated departments with a shared resource that you are required to understand. Sometimes it's multiple messages per day, and I haven't worked there in 3 years. Anacedata as I have only worked at one university.

It's out of control in general. Email itself is a little bit like phone calls these days - almost entirely useless to me as a medium due to the amount of spam generated.

Email is, of course, worse. For every 15-20 emails I get maybe one of them I was expecting or is personal. It's just a glorified spam box.

Those two things are not related. "Give me all the e-mails and Sharepoints on the Exchange server" and "I want to talk to these 59 people" are separate requests.

Presumably the documents and emails come from people besides the interviewees.

Fairly certain that when they refer to “documents” it means pages