I kinda agree with this. I think it's "Don't know / Whoa no!", i.e. the character is alternating between the fact that he's forgotten the message, and his own emotional response to that fact. (The "Whoa" would be pronounced the same as "won't" but without the "-n't" - which if it IS there is drowned out by the music)

Probly impossible to tell which is correct, but I like listening to it this way better.

Go on. Disagree with me. Tell me I'm an idiot. You know you want to.