I took the index from the words, converted the quantity to binary, included 3 zeros, calculated the sha256 digest, took the initial part of the hexadecimal to convert it to binary, additional a few zeros to your eight digits from the binary and obtained 00000010011 which interprets to 19 in https://toplistar.com/story20758093/facts-about-bip39-seed-phrase-word-list-revealed