IMO, the body farm is questionable. The evidence of chloroform may be as well.
Let me preface: the best way to prove/disprove admissibility under Frye is to show other cases in your state where the court has ruled similar evidence/experts inadmissible. I have NOT done the caselaw research for FL. So I do not know how this specific evidence is treated in these specific courts. This is just my opinion "in general" based on a random sampling of cases I've seen/read.
My worry is that the body farm is relatively new, and I am not sure how much evidence has been introduced under these standards. If
Also, I COULD BE COMPLETELY WRONG, but based on what I read here and in articles on some of the chemical reports, the concentration of some chemicals weren't statistically sufficient. For each scientific test, there's a certain percentage of a relevant factor that can be attributed to chance- which is called shorthand the "p" value. If the value of a certain chemical exceeds the "p value," you can say it's most likely not due to chance.
I am sure someone with a much better grip of science/statistics will give a better explanation of that than me. But that's the gist.