We have a serious problem with a licensed contractor we hired to repair dry rot on the front of our house in preparation before putting our house up for sale. Need help!

We have a serious problem. We hired a licensed contractor to repair dry rot on the front of our house in preparation before putting our house up for sale. Yesterday Pest Inspector & Home Inspector stated places directly beside what he did replace are termite and beetle infested! Their comment was there is no way contractor would not have known adjacent areas had a problem. We are two weeks into 30 day escrow. This has devastated us. We are in our 60s, wife in failing health. Now we are set to lose thousands of dollars in negotiations and potentially the lose of the sale of our home. Any advice would be so gratefully appreciated as we are at a lose of where to go from here. Please help