The VoIP industry is full of people who came from a SS7/PSTN/Telco background and have no real clue about network security and Linux/BSD platform system security.
My guess is these are Call Detail Records, not account records.
I'd guess that, too. Does Broadvoice have 350M customers? I'm guessing, but my guess is no.
So let me guess, that my account that I canceled many many years ago is still in that database.
Oh goody, now we can search for who is calling me when caller ID says “Unknown”.
better yet, make a comprehensive robocaller list ... and then speculate as to why the carriers couldn't do it 20 years ago...