"He reportedly hired someone to test if creatine can be converted to cyanide. So he was using at as sort of an alibi, IMO"
Oh, I understood this. What I'm wondering about is him mixing it up and drinking it himself in the laboratory in the days just prior to the murder.
Here is the actual criminal complaint. It outlines his behaviors in obtaining the cyanide and also in the mixing up and drinking the creatine there in the lab.
http://ae3b703522cf9ac6c40a-32964be...riminal-complaint-against-robert-ferrante.pdf
This complaint also gives details on his interactions with her parents both while she was hospitalized and after her death.
In one of the articles it states that there is a rule about not eating or drinking anything at all in the lab and another that lab chemicals are not to be consumed. Also, he would have bought the creatine using grant money so he shouldn't have been using it for personal consumption. That behavior in itself would have caused comment!
He has researched creatine with mouse models for many years now. I can see him telling Autumn that he found it to increase fertility in the mice and her buying the story. That wasn't the focus of his research, but it's plausible that it could have been a finding. With creatine now in clinical trials for Huntington's disease, I would imagine Autumn has heard a lot over the years about the positive properties of creatine.