I am guaranteed this is not user error, since the recovery phrase was located in two different places: backed up inside of a file on S3, and printed over a piece of paper. Standard recovery phrases use a certain list of 2048 words pursuing the BIP39 standard (Bitcoin Enhancement Proposal https://leftbookmarks.com/story19671390/helping-the-others-realize-the-advantages-of-bip39-mnemonic-phrase-tool