I feel like there is a key relating to France that everyone is overlooking and may be rather simple. I'm going to briefly examine a few ways France may be tied into this mess. My purpose for posting incomplete information and speculation is to receive feedback as to whether or not this is even worth spending time delving into. This ARG is tying in a lot more with the real world and real world events then I remember from the original Cloverfield (I followed it pretty closely).
Let's start with the very obvious Eiffel Tower image that everyone is talking about. New Orleans was founded by a company under the direction of a Frenchman, Jean-Baptiste LeMoyne, in 1718. Years later, in 1742, France was 2 years into the 8 year War of Austrian Succession. In 1942, we all know, France was being ransacked by Nazis and over 300,000 Jews were deported and executed.
I don't know if this is applicable, but I'll certainly give it a shot:
I've got the mind of a conspiracy theorist and the reading habits of a history major with no social life. First and foremost, I was tipped off and led by the number 5742, which is the year 5742 AL, or 1742 AD. AL, anno lucis, or year of the light, denotes years in Masonic lore. I would have thought nothing of this, had it not been for the continued appearance of the Eiffel Tower, which was the marvel of the World's Fair in 1889, 100 years after the start of the French Revolution. The Eiffel Tower, in and of itself, IS a Masonic trophy and a mark of dominance that signifies the power of the fraternity to influence society to the point where they created one of the most groundbreaking events in recent French/European history. There is a Masonic tie to the name Jean-Baptiste, relating to St. John the Baptist, but I have nothing further at this time to add to that relating to New Orleans, Masonry, or France. Also, there is the "secret" gift that Megan was given on her "13th" birthday, a number which is very significant in Freemasonry.
I don't know if this is useful information or not, and before I waste any time digging into this for the sake of this puzzle, I figured I'd post what dots I've connected. Yes, I believe this is reaching and splitting hairs, but as an avid reader of history, there were a few things I just couldn't help but point out.
As a fan of the franchise, I hope JJ doesn't include this real-world conspiracy b/s, and as I've been typing this, I have less and less faith in it. But, my inner Ron Swanson loves a good problem to solve. Hopefully I've led someone down a path toward a new clue.
Cheers!