Hello, I am happy to assist you today.
It sounds like the concern of your surgeon has to do with the anesthesia. He doesn't want THC in your system because it may impact the drugs that you will be on for the surgery.
I understand your frustration and desire to get this surgery completed as soon as possible, but it is actually in your best interest to have your blood free from any drugs that the surgeon may be concerned about. I also understand that it isn't your fault and you didn't know it would be an issue. I suppose the surgeon should have had you give a list of all medications you were on, which you may have actually done, and then known that it was an ingredient. If that is the case, then the surgeon did make a mistake, and you could possible have a legal case later on for the extra cost and pain and suffering involved in the delay of the surgery.
Any lawsuit would happen later, though, after you actually have the surgery, so your focus needs to be on how to get this surgery as soon as possible. I would contact other surgeons and ask if they have this same position on THC and whether they might be able to get you in sooner for the surgery. I know that may be unlikely, but at least you can get a feeling for whether your surgeon is following regular procedure, or being unreasonable in requiring you to be THC free.
After you have the surgery, which we do not know yet when it will happen, then you can decide if you are interested in suing for any delay in the surgery and pain and suffering that resulted. This would be in the event that he did not ask you about your medications, or he asked and you provided it but he did not check.
Best of luck and take care,