The next question is about the outgoing Caller-ID Name. From the SIP trace, I see the name is set both in the "From:" line and the "Remote-Party-ID:" line, in quotes (""). However, the name does not appear on the caller-ID box of the POTS line. It seems the phone company (AT&T) is getting the name from a CNAM lookup. Is this something I can change, or is it just not sent in the path between Flowroute and AT&T?

If the phone company is doing a CNAM lookup then there's not really anything you can do, unless they have a reason that they're doing a CNAM lookup instead of using the caller_id_name information. I'd ask Flowroute for feedback on that one.

Just to comment on this:

The norm in the USA is when calls hit the POTS network, there is no name attached. The receiving carrier needs to do a CNAM lookup.

In that case, to have the name show up properly, you need to register the CNAM name.

The exception is: some carriers have direct connections and they skip the POTS system, so they can use the actual SIP Name, as sent.

-Avi