This article was written terribly.
It stated that she made it look like it came from Hadley’s computer.
From what you’re telling me, it could have come from many computers, am I understanding that right?
Right. What most likely happened is they “spoofed” the email. This means, when you get the email in your inbox, the sender’s name and email address appear to come from someone other than the person who sent them.
That really doesn’t tell you anything about what computer they were sent from. It’s just a way to forge what email account sent the email.