Which would be the absolute worst way of going about what you are suggesting - It is the opposite that is likely true - To the true believers, they don't need to prove he is alive (they're other ways - outside of video) - These videos are for the west (and or sleep cells it is worried over).
No, videos using old tapes is to suggest just the opposite of what you suggest (that perhaps he is dead)....And why would AQ want us thinking that???