My understanding is that both are dependent on ambient temp. Since we know she died in her own house, we only need to consider the relatively small temperature range within the house.
Most basements are a few degrees cooler than the rest of the house, which would slow the processes. But only slightly, as the basement isn't "cold", just a "cool" relative to the upper stories of the home.
Then too, she was wrapped in blanket, which would retain some heat.
All in all I don't see that ambient temp played a big role -in the sense that exceptionally high or low temps were present. IOWs I don't see that rigor or livor were retarded/accelerated significantly by temp extremes.
But those of us (myself included) who supposed that the 12 hour rule of thumb should apply may be wrong.
http://www.dundee.ac.uk/forensicmedicine/notes/timedeath.pdf
It seems establishing TOD by rigor is very imprecise.
From the link above, and paraphrasing - Onset is more rapid in children than young adults. It is delayed in cases of asphyxiation or where severe hemorrhaging.
Also, from the autopsy report, "At the time of the initiation of the autopsy there is mild 1 to 2+ rigor mortis of the elbows and shoulders with more advanced 2 to 3+ rigor mortis of the joints of the lower extremities."
So the body was not in full rigor when the autopsy was performed. This might indicate later onset than popularly supposed. OTOH, it may also suggest faster passing of the condition (rigor leaving the body).
Core temp also seems to be an imprecise way of determining TOD.
I don't have a problem wondering what they were doing. IOWs I don't think the staging necessarily suggests they were rushed -except to the extent that no amount of time is sufficient for people who don't know what they are doing, and so would feel rushed.
But it certainly is possible that death occurred later than popularly assumed.
The best reason to reject the idea that the Rs planned to put JB in the suitcase is the sheer difficulty of getting away with it.
What if the pilot couldn't be bought off? And even if he was unaware of the dead body in the suitcase he is available to testify that the Rs took off for Mich. w/o JBR present.
Then there is the additional complication of how to dispose of the body once in Michigan. The suitcase could be dropped in the lake, but who knows what the currents will do with it? It could be hidden in the woods, but when (if) found, do the Rs really want the body discovered in Michigan?
It's possible the plan was briefly considered, but it almost certainly would have been rejected after a few moments consideration.