> In June 2018, the machine mysteriously disappeared
I don't think it's mysterious. The owner likely ran out of full, rare cans of soda and could not / did not want to source them anymore.
For folks who aren't aware your local distributor cans / bottles a much wider variety of product than what you find on typical grocery store shelves. If you have a commercial account with them you can get the list. Sometimes they make special runs for a promotion, special event, or special client order. Depending on the circumstances and if you have a good relationship with your sales rep you may be able to get notified and grab a case or two.
It is possible they were vending long expired drinks... but it is also possible they simply had a hookup at the distributor and sourced rare drinks from time to time.
Works this way for tons of things. People would be surprised the kind of things you can get by being generous to sales reps.
Supposedly, you could order Crystal Pepsi, but nobody did, so none was made (except for a brief period a couple years ago).
I stepped into my office 6 months after covid WFH started. All the unrefrigerated sodas were flat.
I doubt they had expired drinks with no complaints.