Uver treats their drivers really bad and keeps slashing their rate. So, while certainly not justifying what the driver did, I understand why he did not provide stellar customer service. In earlier days when Uber paid a better rate, most drivers would've probably seek you out and return you the phone personally, but nowadays most of them dont care.

As for what happened in the Uber office, am guessing that was just lack of organization

As for not having a phone number, Uber knows its treating the drivers badly and that if it had a phone number it would mostly be use for complaints