Does plant material oxidize from 02 gas (air or solved in water) and/or oxygen in H20?
Okay first, it's the oxygen in the air that causes oxidation, also dissolved oxygen in water, but if you let your tobacco get wet enough for the latter to be significant you will be getting more rot than curing ...
Anyway, I don't think a sealed jar would be a good idea. Ammonia build-up, wet rot, etc would tend to be an issue.
You could build a proper curing/fermenting kiln to cure the leaf, there's DIY instructions here: https://www.seedman.com/wkiln.htm for one type.  But if you're using the finished product for dry snuff rather than smoking or chewing, you might not be too bothered about the taste/smell so careful fermenting is probably not that important to you. Then easiest is to just hang them somewhere like the garage and spray them with a plant mister when they get too dry like this guy: https://dengarden.com/gardening/Tobacco-Growing-and-Curing-at-Home or if it gets too cold where you live to use the garage, in a closet, wooden box or linen chest.