Begs the question.... 'Why did she keep an out of date pass if she has a current one?'
Whenever I'm sent a new card (for travel, bank or whatever) I always keep the old one on me until I've tried the new one and ensured it is working. I have to be absolutely certain before I cut up and dispose of the old card.
And yes, that has occasionally led to producing the old one mistakenly, though I've always then had the new one to produce instead. But if she is someone who tends to be anxious, as many of us are when travelling, then the mistake is understandable.