I can't answer all the questions but saturated salt water should boil at about ten degrees higher than water, so about 222-225 F so you're thermometer is ok. That part is physical science. Are you going to try to resaturate the brine? and if so then you will be able to tell how much salt was lost and how much cheese absorbed it, right? I am just wondering how much it is going to take for future reference since i don't have a salinity tester.