Theoretically, could the founder of Yo have pressed charges against the student? (This would, of course, be complete suicide for any startup. But companies aren't always rational actors.)
In fact, what those guys are doing increases the collective conscious and improves the system to be able to develop better/safer products.
In fact, it seems straightforward to make a case against the student's activities. From the Computer Fraud and Abuse Act:
(2) intentionally accesses a computer without authorization or exceeds authorized access, and thereby obtains—
...
(C) information from any protected computer;
The phone numbers are probably information from a protected computer.
Young people are pretty often cavalier about jeopardizing their futures. I'm just checking whether there is, in fact, a chance that this young person could have.
If it's not yours, don't mess with it.
Does anyone remember this case?