I know that the people on In Session are saying that Lee and the other doctor show a patter of doctor shopping and Michael was looking for anyone who would give him this drug, regardless of the warning. The problem being, they're ignoring the time line. Namely, Michael asked about different drugs during the time Murray was loading up on propofol. He found a doctor, so why would he continue to doctor shop.
Although, one of the lawyers was smart enough to mention that there really is no evident that Michael was physically addicted to anything since his liver was healthy. She also pointed out that this doctor and nurse said no, unlike Murray and kept medical records of what they gave. I also don't see how it's doctor shopping if you knew one of the doctors for 15 to 20 years and should know what they will or will not do by now. Lee also showed a pattern of self-awareness and how he did try other things and didn't go stay to propofol.