Oh no! Poor Zeke and poor you.
Is pano one of those growth problems in large dogs that is affected by diet? Or could be helped by diet and supplements?
Back to your original question about withholding pain meds, I think he definitely needs something to control the inflammation and for pain management, whether that is a natural product or an Rx from your vet. Nana had very good suggestions for the herbals and are the same sort of ingredients found in products like Dog Gone Pain that you can do formulate on your own without purchasing a product, but those can upset the tummy. I had good luck with the DGP for Chi and Dixie with injuries and joint issues, and when the retired nurse and others at the health food store looked at its ingredients, they agreed that it was a nice product and an interesting combo of ingredients because it contains both herbals and enzymes, whereas other products are either one or the other but not both.
I hope you find something that works for him and that he gets out of this phase soon!