I could have swore I saw them in green/gray camo but I’m not finding any pics of any real ones like that and I’m seeing up references that this may have been a test case on one or maybe just a few aircraft.
That is correct, no operational F-15E used the Euro Green Camo scheme. I’d like to recommend a book called The Great Book of Modern Warplanes, This is a huge hard cover table top book that is a must have for all modelers. It covers all modern US warplanes and has a very extensive section on MIG’s. It has everything you ever wanted to know about the F-15 and all its varients. I have used to this book to help me turn out some awesome models. I plan to get another copy of this book ASAP, since I had my last copy stolen.
I actually have two copies of that book; a 1985 edition (without the section on “America’s Stealth Fighters”, and the section on MiG’s has some pretty fanciful drawings of the then-unknown MiG-29), and a 2005 edition. Both are invaluable resources.