I've had to do it before, also for a gift-card-related problem (different from yours), and I was contacted by a member of the Apple executive escalations team a couple days later.
I did read about part of the product development org having a standup about trending social media cases, and prioritizing followup on items that were under public scrutiny.
Believe me, I have no desire to defend Apple. Their behavior absolutely sucks. I just want a good resolution for the author of this blog post.
I imagine it could be helpful to other people in the same situation.
Obviously someone either at Apple's gift card printing contractor or at UPS snatched it.
Apple's suggested "solution" was for me to issue a chargeback on my credit card -- yes, the vendor suggesting a chargeback. I refused, because the credit card in question was my Apple Card, and I have read elsewhere that doing something like this can lead to your Apple account getting locked.
The exec escalation was the only way I got it resolved. It was Kafkaesque.
I think one major lesson to take from this (and other physical gift card vulnerabilities, like people that go and peek at the numbers on unredeemed cards in stores and then wait for them to be loaded) is: don't use physical gift cards anymore.