As you probably realize, those numbers are the original sample rates of the digital PCM incarnations of the master(s) which were subsequently MQA encoded. Analogue masters which have not already been digitized (or where the studio has chosen to go back to the original analogue tape) must be digitized, which can happen at any rate, but 192kHz seems to be the most common rate for material recorded in the analogue era.
In some cases, there may be more than master (e.g. original version and re-mastered version). Sometimes this may be obvious (e.g. Rudy van Gelder editions of certain Jazz classics seem to have original sample rates of 44.1kHz, but the originals are usually 192kHz).
In other cases (perhaps in the Norah Jones example you’ve posted), as has been mentioned, some studios do appear (unfortunately) to producing MQA encodes from different sample rates of a single master, probably to sell them at different price tiers. One has to hope that they are down-sampling a 192k master and not up-sampling a 96k master; according to MQA Ltd., the MQA encoding process does look for – and flag – any up-sampling, though I suppose it’s possible for the encoding supervisor to override such a warning. Personally, I go for the higher of the two numbers; I hope I’m not wrong to do so.