The early autopsy results had no inkling of chloral hydrate in the results. Its' use had to come from "a tip".
I'm inclined to think that the chloral hydrate was NOT out in the open at the Hardrock. Perper said something new came to light and they were running more tests. After those tests came back, the whole of the pending autopsy results changed. "Death by Chloral Hydrate".
Well, OK - *we* the public didn’t know about the CH until after Anna died, but it was March 16th on ET - when I waited a whole weekend, lol, to see the segment again on a re-run - to catch the last drug name on the infamous fax list (a different one from the one tmz published).
The drug name had not been mentioned when the first view of the fax list came out. Then when ET did a 2nd installment of the Dr KE segment, I was able to see the graphics with the drug names printed out and chloral hydrate was the only new one I hadn’t been able to catch on the first run-through because it was “new” to us and unfamiliar in general.
It was so ironic (maybe!) that it made such a big impression on me, then later became “the” cornerstone drug.