Personally, that is the sort of memento that needs framing, and hanging in a place of honour, like the dunny.
However, to fix the immediate lounge problem, I would have gone to one of the CX transit counters, said "this is me Mr Diligaf, seated in 1A, I appear to have lost my boarding pass, please may I have another".
I bet Gladice or Mabel would be quick smart to issue another boarding pass, without the biro scribbled N/L defacing it.
The contempt this company shows its pilots has no bounds.