looks like the Roush dealer either passed the buck to the first owner regarding the mail in warranty (dealer is supposed to complet and send when sold new) or the first owner said they would and didnt..lol
Its no longer valid, but nice to have the original docs.
If you call roush, they will have some info (limited btw) on your build by tracing their Vin. I assume your truck has the Roush vin tag in the door jam.