The first thing I"d try is searching /Library/Receipts/InstallHistory.plist for the applicable one - if, in fact, there is one - and deleting it to see if it triggers the App Store.
Failing that, Apple owes you.
They didn't do a complete job of replacing the logic board and owe you either a new board or, at the least, the update.
How far away is the Apple Store?
Last edited by artie505; 12/25/20 11:45 AM. Reason: Add path