Hello there. My name isXXXXX and the good news is that oreo cookies have such a small amount of chocolate in them that even this amount in a dog Sawyers size is not really a concern. The bigger concern is this amount of cookies causing an upset tummy while passing through. You could see vomiting or diarrhea over the next few days so monitor him closely. If he does have either or then feed a bland diet such as boiled chicken and rice or boiled beef and rice until everything starts to settle down. If it does not clear or if he is lethargic then make sure to have him seen by your vet. There is not much else I would do. Even if he does not vomit tonight I would not worry. I actually would not recommend inducing vomiting on him because there is more risk with vomiting then the cookies he ate. I hope that makes sense.
Thank you for your help
You are very welcome. Please do let me know if you have any additional questions or concerns I would be happy to help. Please do not forget to rate my response. thank you!