You are represented by an attorney to no reputable attorney online should interfere in your attorney client relationship. Ask your lawyer. He is far more familiar with the situation than anyone here that reads your six sentence post.
As the other answers indicate, you should go over these issues with your attorney. Perhaps a continuance of the trial is in order due to the potential surgery. You would probably have to have the surgery scheduled to get the continuance. Normally, a settlement is not finalized until you sign the release or some document confirming the settlement or put the settlement on record in a court of law.
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