Yep, it's all true. However, don't forget that FFE was released in an unfinished state by the publisher (which lead to a lawsuit between DB and GameTek), and many possible branches of the Thargoid storyline were unfinished and/or not working. As such, it would make sense that Frontier would now rather retcon the whole thing. Even the most finished scenario, where the player would choose to aid the Thargoids, had some pretty serious bugs. Also, at the end, your Alliance handlers would tell you that you were outlawed in the Empire and the Federation, but nothing of the sort happened.
It could also be that the canon ending was where the player would side with INRA and betray the Thargoids, by not delivering a mycoid vaccine, but instead an improved version of the virus to their world in Miackce. That would certainly explain the cover-up since then, and why the Thargoids have disappeared. This would also mean that the later journal articles (listed on Jades' site) would be invalidated, of course.
In any case, back to something more relevant to the topic on hand: looking at the artifact from the video, I'm fairly certain that it has something to do with Peregrina. It does look like some kind of seeding mechanism. It would be entirely possible that Peregrina's moon became a plague world due to some Thargoid experiments - or maybe there is no plague. It could be an INRA cover-up of something else that's on the world. (It'd certainly be an efficient way of eliminating anyone who might have stumbled upon something there.) Also, it's a terraformed world according to the system map - why would anyone terraform a plague world?
Besides, the system's description specifically mentions alien artifacts, so I'd say it's still a prime candidate for looking. I've just fitted a cargo scanner and heading back there.
