The main problem is fungus growing on seeds that were not well cleaned. Pulp sticks a lot to the seed and is hard to get completely off. If they do a good job of cleaning them then the second problem is that they start germinating in transit and they are seized by USDA, as germinated seeds are not allowed without a phyto.
So if you can get an excellent packer, they clean immediately after opening fruit, use very little moisture in packing, and use EMS shipping, then you stand a chance. I suggest you make a small order to try it out first.
Strangely enough some of the other species of durio last longer in mail than regular durian. So you have a better chance with these..