The "classmate" of Lanza's seems odd. Notice she never even knew the guy, yet describes him as "distant" and a little "off". She says, oh yes, there were signs he was a genius, but she took no classes with him nor had any personal anecdote to share about it. Again, she just says something about he "seemed above" everyone else.
I just don't get any sense of sincerity from her. She does not seem like a nervous student expressing her (apparently, lack of) knowledge. Seems like she had talking points. He was a loner. He was quiet, etc.