to EBN .... THANK YOU FOR RESCUING!!
You can either do a slow transition to Orijen, like 5-7 days or place him on a bland diet for about .3 days and then switch to the Orijen. Also, keep in mind, he will need some time to settle in to his new home, so he might not eat or might even get the from nervousness for a few days. if he does, add a little pure pumpkin to his meals to help firm up the poo
Good luck and be sure to post some pictures