Thanks for posting this interesting article. I thought this bit was useful to hear:
Blood, urine, bile, ocular fluid, gastric contents, liver, and brain tissue can all be useful specimens. Peripheral blood (femoral or subclavian) specimens are optimal for postmortem toxicologic quantification; urine is the primary body fluid used for drug screening. Specimens need not necessarily be tested automatically, but the best practice is to at least collect and hold the specimens until completion of the autopsy report and death certificate. Sometimes, additional history does not become known until after the body is released, which is then too late to collect samples.
So, clarification that there's no point in trying to get new samples from MJ's body now - other than to make a darned good bit in a movie that is!