Well, the dx10 proto was thrown out so neither would look like it. We never saw the revised dx10 proto but it more than likely looked exactly like the dx13 proto minus the battle damage.
I've posted this probably several hundred times and the only counter argument is basically, "I think it looks different, therefore it is." Any differences one can see (between 13 proto and 10 production), well, I've explained why enough times. It's the toy business. I'd start thinking I'm being trolled here, but I see it's not just this thread where people can't seem to accept/understand proto vs production and part reuse.
If anyone has an explanation why the DX13 would be a different sculpt, I'm all eyes. Hell, I'd love to see someone explain the process.