Well, this isn’t strictly a YouTube LOL as much as it a Metal Injection LOL but you get the picture. Or the video. Or whatever. Shut up.
Yes, this is actually Hanson covering Slipknot.
Here’s what Metal Injection says:
Has Hell frozen over? Here is footage of Hanson jamming in their hotel room to the Slipknot track “Wait and Bleed”. This was part of an April Fools gag where the band of brothers announced that they would be releasing a Slipknot covers album. What’s worse, this or the Bieber mashup? [link].