You're talking about Dee Dee as if she were a student being graded on an assignment instead of a witness in a case.
If you or I lost a friend in a homicide, we might feel that getting obsessive about the case was the best way to deal with the grief. Many people would do the opposite, and avoid the subject as much as possible.
It's also questionable if it's the right thing for a witness to do. Researching the case might contaminate her recollections more than it clarifies them.
I just don't think she much intended to be a witness, if you listen to Team Crump. First there was the story of the investigator from Natalie Jackson tracking her down. From Crump, it was Tracy Martin who called her Sunday (3/18?), he called her on Monday and Tuesday he has the presser.
Then why the delay if he was her friend? She is so upset that she has to go to the hospital on the day of his memorial (either the viewing on March 2nd or the service/internment on the 3rd) but she still doesn't tell anyone what has happened? This was her good friend. She knows the family has been crying out for answers. Not only is it a statewide story, the nationals have picked it up also. Still, nothing from Dee Dee. His father tracked her down from looking at the bill. (Sorry, I don't believe any investigator found her.)
I can understand her reluctance with LE. But there was not some friend or some adult she could have trusted enough? I don't find that plausible.
I also question when Tracy Martin actually contacted her. On March 5th, he declined to allow access to TM's cell phone as per request from Officer Santiago. He said he "would contact his lawyer" before releasing that information. Crump implies that the first contact with Mr. Martin was Sunday the 18th.
Considering that she was under the wings of Crump for over a week before the meeting with de la Rionda, "Student" might very well be a good description of her, IMO.