Are you serious? Here are your "death threats":
I don't know. First off, what Maja is talking about is
before the accident. The way the sentence is phrased makes it sound like it was something that happened at least a matter of days ago, not about 30 seconds after the fact.
Secondly, you really think Marla said anything about that when she was the one who pointed a gun at him? And you watch too many cop shows. I really doubt the police is going to ask about the victim's enemies, from the very woman who hit her.
Third, if it did happen you can bet on MC being called into questioning or at least have a cop show up at his house. This didn't happen, ergo, there was no statement about Nika ending her life.
And even if the cops decided to leave him alone. And the eyewitness report came to Maja. I really doubt she would be dumb enough that, when Nami told her who he was, that she didn't recognize him (yet still managed to remember that there was a death threat)
Therefore, it only stands to reason that a recent death threat was made against her,
not by Nika.
And for the other guy, maybe it could have been but certainly not for what happened in highschool. I don't remember if the bully came into her life in the recent chapters - then it could have been her - but I doubt it.