I’m sorry to hear this, he is a very well bred dog.
You might want to have bloodwork done before and after using Rimadyl to check his ALT (liver) numbers as some dogs can have a bad reaction to Rimadyl and it can affect their liver. My old dog cannot take it, which is shame as it does work well for many dogs. Just wanted to mention this.
Best of luck with him and I hope you can get him fixed up.