Airline staff are the final arbiters. They may seek input from immigration staff, local or at the destination, but only on an advisory basis; ultimately if the travel documents are not acceptable to border control staff at the destination, the airline picks up the tab.... AL is not a passport authority, and an independent arbitrator might come to a different conclusion than AL's check-in staff on the validity of the passport...
In this day and age it is reckless and irresponsible to try to use travel documents that are not perfect.