yes you can potentially die from just drinking pure water if it is enough of amounts in short time. like 3-4 liter in 15 minutes and you walk with the dodo.
the person ate 1 pound(? was it pound? or kg?) of that cashews a day, that might have been too much. if she had cheese along it, maybe it wouldnt have happend?
but i will look now more into those oxalates.
what i find funny, she describes how physicians work in the clinic... kinda dr house approach... taking symptoms serious and if they do not find something walk through the list until they do.
this is not a practice i experienced in german medicine, usually they have 1 hyothesis and if it isnt that, its either psychosomatic or migraine or some other useless diagnose flagging you for other doctors not investigating anymore.
if MDs would work like she describes only 50% , i would have much greater respect for that profession.