Thawing or not thawing the body - there are ways of determining ToD in frozen bodies. Time to freeze and time to thaw are not particularly important to those calculations.
I wrote a long post about it, but to summarize:
Different parts of the body freeze more quickly. Deeper organs freeze last. Brain will show visible signs (upon tomography) of hypothermia and then freezing. There are charts and calculators that medical examiners use to compare all this data (first subtracting, of course, the time it took for the body to entirely freeze). Weather data is used as well.
Then, there are enzymes produced by dead cells (which will be dying at different rates in a human body - most likely fingertips first). Usually, samples are taken from 4-5 different organ systems. Decomp still happens, even in deeply frozen bodies (like the Iceman found in Italy). It's just way slower. There are ways to learn just how long it took (bloating, for example, may still happen in parts of the body at temperatures like the ones we have in this case). The gases in the bloating will be frozen in place as the body freezes. Upon thawing, samples are taken that give a good picture of the process of death.
None of this depends on the body size of the individual. It's all biochemistry of death.
IMO.