The original report is
here.
While I had not completed my investigation, I am inclined to believe that, based on the information provided, that even if the appropriation of wording and paragraphing is mostly coincidental, the flavor of the paragraphing suggests that at least in each case reported, the overall arc of the orignal fic was being reproduced.
While this is probably not plagiarism per se (e.g. in the Hunger Games, many fanfics often follow the basic template of the first book, or follow a "Reapings/Interviews/Games" arc; in Harry Potter, phrases from the canon material are often reproduced verbatim with attribution given to JK Rowling), what does suggest to me that plagiarism has occurred is that the author made no attempt to rebut the case even though I invited them to do so:
Hi,
I would like to let you know that a couple of your fanfics have been claimed to be "lifted" in terms of story elements and text from some older fics, and that report is available on the stop-plagiarism livejournal community. I am the moderator working on that case and invite you to make your own case either by PM to me or by comment to the LJ community.
Instead, Jaden Anderson changed their ff.n handle to Done.Writing.For.Fanfiction and deleted all of their fanfics. This, more than anything, suggests consciousness of guilt to me based on the timing of their deletion of fanfics (which was less than 2 hours after I PMed this person) and their claim to me, reproduced here:
There really is no case to be made. I see the report and can definitely understand. What was done was not intentional, and the stories have been removed. As you can see, I have not been writing fanfiction for months now, and have decided to remove the account. I hope this clears everything up.
For the record, I now include "before" and "after" shots of their ff.n profile (clickable thumbnails):
On the basis of the above, Jaden Anderson will be added to the list of known plagiarists.