Redleg: I don’t think there’s ever been a standardized spelling in Yiddish, any more than there’s no standardized spelling between American English and British English. Yiddish has at least as many differences and variations as English, is not (many) more. And legitimately so.
And to the extent that there are spelling errors by some Yiddish speakers so are there spelling errors among English speakers. Neither are the norm. Not among American English users, British English users, Chasidish Yiddish users or Litvish Yiddish users.
And YIVO is meaningless and full of hot air.