If it was a decade then the Armory that you are trying to make it work is the old version of it you might be using v0.90 or below.
There is a new forked version of Armory developed by goatpig and take note that there are no seed codes you may be referring to rootkey there are 5 backup types when restoring the paper backup.
Since it was an old version of Armory the backup you have may contain "rootkey" and "SecurePrint" If you don't want to download the full blockchain you can simply install the most recent Armory wallet and import your backup and then backup it again from Armory but this time choose export key list to backup only private keys that you can import to Electrum it doesn't need to download the entire blockchain so you can send BTC right away after import.