Has it ever been explained why this alleged vaccine needs to be kept at temperatures not found in nature?
It is an RNA vaccine. RNA is much less stable than DNA for a few reasons.
The main one is that Deoxyribose (the D in DNA) is missing an oxygen atom when compared to ribose (the R in RNA). That oxygen atom, as part of a hydroxyl group, is very reactive and tends to combine with other elements and break down the RNA quickly.
DNA is designed to be very stable and last a long time. It is nature’s long-term information storage.
RNA is designed to be used quickly and temporary. It is a set of instructions for immediate work, not storage.