I'm confident this isn't user error, Because the recovery phrase was found in two diverse areas: backed up within a file on S3, and printed on the bit of paper. This post points out BIP39, the standard that defines how seed phrases are created, and summarizes how BIP32 and BIP44 https://binksites.com/story8550807/an-unbiased-view-of-bip39-seed-phrase-github