I do like that you drew attention to her family, but I am less sure if ir would be made to the news, plenty o children dies or go missing and not all cases gains media attention. I confess a lack of knowledge here, but does Nika don't know or don't remember ? Summer goes missing some time after the cabin, she was out to a travel, maybe the whole family died in a car accident or something. Maybe is not about the Nika's infatuation, but the mysteries that of his past, there is 100 ways to explain why Summer is gone.
I like the idea of witness protection, but I also don't. From a plot perceptive I think it works, from a character one less so. I think that whatever happened to Summer should be tied to Nika in some form, not that he need to me responsible but something he would feel responsible for, I just can't see a 14 years old boy losing himself completely over a teenager love that don't seemed to have lasted very long. I read it as a tragic and witness protection don't quite hits the same note.
Also I am less sure that Summer family is of any relevance, to be worth witness protection.
You are right again about the family, just want to say that I find odd the reluctance that of Nojiko and Nami to talk about what happened, I mean, if she simply died why they don't say it, " after Summer died". When we are at Vic's Nika explicit says that Summer disappeared, so I don't think she is dead. I have flirted with the idea that she was comatose, but now that we know about Bella sisters it feels to repetitive, unless they are somehow related. Maybe they made a plan to runway but Nami stopped Nika but was alredy too late for Summer ?
I completely agree, Summer should remain absent, bring her back don't adds nothing but cheap drama and lessens the story themes.