Cap from a Fuddy plane crash video.
This is an infant life jacket. Looks like it has been cut through with a sharp knife. Has her name on it but she seemed to be in a full size life jacket when she goes into the water.
Something not right. The diver theory was prevalent when it first surfaced but it would have been hard for them to put down right on top of pre positioned divers. Conspirators on the plane more likely to oversee her drowning.