Hi Cynthia,
I'm not sure I'm completely following you....
Yes, natural hybrids are found in areas where the species parents overlap and, definitely yes, a x guatemalensis could be polinated from another x guatemalensis making 3rd, 4th, etc., etc generation x guatemalensis. A x guatemalensis could even be polinated form another C. skinneri (and I believe it would technically still be called x guatemalensis unlike in artificial hybridizing where this would be a different grex).... Am I missing a piece of the puzzle you're trying to put in place? I've had a long, intense orchid weekend (approximately 24hrs spent over the course of the weekend at the auctioning off of a major collection - more than 1200 plants) so maybe my brain is jsut a bit fried...
My near future ==>
Feel free to pound the point into my head if you wish.
On the up side of things, my time at the auction was well spend and I picked up some spectacular plants.