I think this is something that can often backfire. If someone creates evidence that say's the plane crashed at location x, when location X is searched and there is no plane, I still have more information than I started. I know the evidence that led me to location x is incorrect. This could be because the data is bad, or due to tampering. If I'm now focused on tampering and able to corroborate that it is tampered with, I now have a new area to narrow my investigation, based on who has the skills, ability, and motives to tamper with that data.

Now, I would agree, if the goal was to create a short term disruption to the investigation, which didn't require holding up to scrutiny in the long run.