I took the index with the words, converted the number to binary, extra 3 zeros, calculated the sha256 digest, took the main Element of the hexadecimal to convert it to binary, added a few zeros to the eight digits of your binary and got 00000010011 which interprets to 19 in https://social4geek.com/story4414244/getting-my-bip39-words-to-numbers-to-work