This, and also even when it was top 10%, that only accounted for about 20-25 (depending on class size) of the ~42-45 people that LR takes every year, so there are/were many more people who write-on. And a handful of the people who graded on will transfer out anyway, so it ends up being mostly people who wrote on.
My class was something like 350 people and top 10%, so there definitely weren't a whole lot of spots left for people writing on. But meh. I'm still bitter years later because I ended up close to the top of my class, yet don't have LR on my resume because I bombed my first semester and couldn't write on. Part of why I'm fairly unsympathetic to someone who decided not to even do it at all. Don't mind me too much.
I agree that you should immediately contact the secondary journals and ask if there's an alternative way you can get on. The 1L class is small and had surprisingly low participation in write-on, so journals might be open to this. Can't hurt to ask.
If I remember, the journals, despite being student-run, all have faculty advisers, right? I suppose OP also could try going to the faculty advisers for the secondary journals if she has any connection with them. I remember reading about something happening awhile ago where faculty got involved. Can't recall what, but there was some issue with students and faculty forcing the journals to do stuff.
Somebody seriously failed at their job if the 1Ls didn't realize how important write-on is in the law school experience. I mean sure it's stupid that it matters but I don't regret the work I put into my publication and especially not the one week of write-on which was NOT THAT BAD, GUYS. Did they not have an info meeting? In my year it was essentially mandatory to do write-on and almost nobody didn't write on to one of the four. It's crazy to me that so few people would do it.
Yeah, write-on really wasn't bad. I think people could do it in their sleep and still get onto something.