To be honest, some people like hybrids and some don't. I am sure that if you could get them to breed you would very likely get fertile offspring based on what I have seen before.
Somebody else will certainly have more information than me on this as I do not work with hybrids. It think the trick is to somehow get them to want to breed as this is somewhat un-natural and they will not want to do this for you.
The only thing I would ask of anybody working with hybrids is that they keep things straight and clear for any buyers. Too many times I have seen obvious hybrids (albino "thayeri" or "Mex-mex" for example) sold in very misleading manners. And in some cases a hybrid pairing can throw out an animal that looks like a pure representative of the species. That is the big rub here with people that wish to work with animals as a species or a locality, is that it complicates down the line providence.
Lance
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Herp Conservation Unlimited
If people really learn from their mistakes, I should be like the smartest guy in the world 