Very good chance this is fake.

But if it isn't, the people behind it can use a commit-reveal protocol to prove the tape is real: cut the video into n different chunks, and commit to those chunks with a merkle tree. Then publish the merkle root, and say that on BTC block x you will reveal m<n of those chunks, picked at random with a deterministic algorithm using the block hash as a seed.

There's even a way to turn this into a payment scheme to get paid for revealing the data: https://github.com/unsystem/paypub