Oh! If you have the fossil you can just save, extract, then if it's male, just reload the game and try again with the same fossil! I just did that today.
Natures don't matter to me. If you really can't get a female, then it's OK though. :)
Hmm, no I looked it up, eggs don't work. Do you want to breed one for me then? A fermale one would be great, but I don't know if you have the time to breed until you get a female one, lol. Well at least you get to keep all the other ones but still...