ATS.X: Project Serpo: Revelation Or Hoax?

I've admittedly only just heard about this Serpo business, but already I have a major problem with the basic story.

As I understand it, the claim is that a Roswell alien survived in 1947, went home, set up an exchange program, and most of the people who went died from excessive radiation due to the binary star system.

Here's my problem. As I recall (and I just re-checked), Z1 & Z2 are about 5500 AUs apart. That's 5500 times the distance between the Earth & the sun. Pluto's just under 50 AUs from the sun. How could two G-type stars at that distance cause such radiation?

I'll look into it more, because it's an interesting concept, and probably would make for an okay movie on the Sci-Fi channel, but I'm leaning toward hoax on this one.