The hand written address and lack of return address on the envelope didn’t faze me at first; but when the letter was about 2 free airline tickets they did seem odd and my radar detected some anomalies. When it said, “We have attempted contacting you several times without success” I thought “They must not have been trying too hard.” A single sheet of paper that is kind of crinkled doesn’t seem too official, especially for something the VP signed by hand. I rarely travel by plane (getting there is half the fun!) and the major rule “If it sounds too good to be true it probably is” definitely leads to Google.
Yep, I was right! Everything I found says it is a scam. 2 points for me! 
If I’m bored later maybe I’ll call and play along just to badger them. I actually do happen to have a pre-paid cell phone if they are also phishing for phone numbers.