I took the index of your words, transformed the number to binary, included 3 zeros, calculated the sha256 digest, took the first Component of the hexadecimal to transform it to binary, included a few zeros for the 8 digits in the binary and acquired 00000010011 which translates to 19 in https://yesbookmarks.com/story18954016/getting-my-bip39-words-to-numbers-to-work