My only comment on this type of situation is this: In our day and age of technology, there is not an excuse to leave someone hanging. Send a text, leave a voicemail, or whatever. But do something! Don't leave someone hanging. These type of situations invariably start with "I'm running late." And they seem to end with...nothing at all. No response whatsoever. Frankly, if it starts that way and finishes that way, to a guy on the other end it seems to be a lie.
I understand. It has happened to me. But a simple text "Sorry, not gonna happen, but I'll make it up to you" will at least let the guy know what is not gonna happen. Or at least it isn't gonna happen then!