@NeoFit
The "tampered flight recorder" argument was based on a misreading of the data by the independent investigator hired by Asseline's SNPL team, which amateur investigators tied to a photo in which a Swiss photo expert said the two sets of flight recorder casings were different.
The problem with the latter is that no-one from the investigation ever said that the cases in the photo were those recovered from the aircraft - they may have been "dummy" units shown to the people working the site so they knew what they were looking for.