I think this has a strong hook, but then a lackluster follow through.
The individual details we get in the first addendum didn't come together for me to actually piece together an image or a theory from the negative space. We get a few details about the actual signal itself, but I didn't feel like there was enough in the first collapsible to build up much about the signal that the original message paired with "Reggie is OK" does not already accomplish.
While I understand that the explanation is meant to act as a false herring, I feel like too much time is spent detailing logistics to create such an explanation. This time might be better spent trying to add to the atmosphere or give more meat to the mystery of "what is wrong with Reggie"?
The ending has a nice twist in concept (namely the idea it is a live feed), but I feel like there's not enough significance attributed to that for me to feel the shock and awe from such a revelation. I think that, this could work really well if the ending gives the reader more hints about what Reggie is, and what is wrong with them. Not concrete answers mind you, but enough information to make the reader start asking questions.
I think the idea of people amnestizing themselves and re-opening the file is also clever, but I wish it was built up to more. The realization we've done this before did not hit me very hard because I didn't get a sense of stakes. Since I don't have anything concrete to latch onto regarding Reggie, or the implications of Reggie's call for help, I don't feel the significance of having reopened the file.
Overall, I think this article has a nice concept, and a really solid hook. I just want the mystery to feel more full. I want to have more questions about reggie other than "who is he?" and "what is wrong?", because right now there's not enough here for me to feel super invested in those answers.