After doing further research:
No, it is not. Originating at CreepyPasta, a site for creepy stories, Buried Alive was another creepy story, such as Lavender Town Syndrome.
But, here is a video of Buried Alive being fought!!!1!1
There are many discrepancies in the video, such as a Level 40 Charizard getting a critical hit every time when the chance was based on Speed, and a transformed Mewtwo doing far more damage to itself than the actual Mewtwo does.
It is not real, and there is nothing to worry about.