I am with you I would get second opinion from a total different office than the one your mother in law is going to…maybe they can get a better sample to test …. Just with what that dr said I would not have surgery…. Sometimes we need to advocate for our loved ones …. I have been through it 2 tkr same knee year apart…. Needless to say i am big on second opinions and explaining of exactly why and what may have went wrong the first time so can hopefully prevent things from going wrong….