How can I fetch an NFT's
updateAuthority without using
you could also look at using metaboss to decode the specific nft mint youre looking to work with and from there recover the update auth.
have a look at metaboss here: https://metaboss.rs/decode.html
metaboss will also allow for pretty much any NFT functionality you would like to have through the command line.
You will probably have to parse the output yourself to recover the update auth any other info u needed
getAssetsByAuthority from DAS API through Helius