Once he suspected what it was he made no effort to return the device, but made a good deal of effort to sell it to a tech blog. Err... excuse me, his lawyer wants people to say share it with a tech blog.
HTC have a lot of phone models, Apple has exactly 3 which most tech savvy folks could identify readily.
Since Apple only has 3 models identifying an Apple phone which is not one of those models is much easier and strongly suggests it's a prototype particularly since Apple is based near the bar in question.
HTC isn't they are based in Taiwan (which most people on the street probably wouldn't know).
Before I would leave word at the bar, on the theory you would backtrack.
After I became aware it was a highly sought after prototype I'd extend that to the local police and I'd try to contact HTC but probably fail because they don't want Joe Consumer calling them.