I don't know much about those saddles, but in general, I avoid cracking in the leather unless it is very minimal and not in a load bearing area. This is usually dry rot, which is not repairable (other than replacing the leather part). If it's only on the billets or stirrup leathers, those are at least fairly easy to replace, though make sure you consider the cost of this. Dry rotted parts must be replaced before a saddle is safe to use.
Tug on anything at all and you'll find it connected to everything else in the universe.~John Muir