There are separate laws for video and for audio. Recording video is allowed in most places; audio recording is much more restricted, and as far as I know making this recording was not legal if it was in California. However, litigating it would cause so much more PR damage that it will almost certainly won't be.

You agree to surveillance when you use these cars.

Intent matters - as soon as the recording is used (and published!) for a clearly different purpose, the legal situation is quite different. For example disclaimer similar to classic "your call may be recorded for quality control purposes" may allow the recording (depending on the location, etc) but generally will still land you in hot water if the company publishes that for an unrelated reason.

No you don't. Show me where that's in the terms?

Some states make exceptions for recordings that take place for business security purposes. California does not.

However, CA does make an exception for recording "in any other circumstance in which the parties to the communication may reasonably expect that the communication may be overheard or recorded."

You could certainly make an argument that this douchebag might reasonably expect audio to be recorded in his company's driver's cars. Not so sure you could make that argument for the other passengers.

Interestingly, Bloomberg could be sued (or prosecuted; $5000 fine) for distributing the recording if it indeed falls under CA's wiretapping laws.