The Medical Report points out the coolant had methanol and the crash site itself contained ethanol prior the crash:
The fuel used by the accident aircraft did not contain ethanol or methanol. The accident aircraft had a modified “boil‐off” cooling system that contained methanol. There were alcohol (i.e., ethanol) containing beverages in the box seat area of the viewing stands where the accident aircraft impacted the ground.
as well as:
Methanol is produced postmortem, along with ethanol and other alcohols, in the putrefaction process. Methanol, commonly known as wood alcohol, is metabolized to formaldehyde. If ingested, the toxic and lethal levels of methanol are 10 mg/ml and 150 mg/ml, respectively.
Given the methanol level established was way above the lethal level, I would not read too much into the Toxicology Analysis, unless you really know what you are talking about (which I do not)
NoD