Matt,
show vlanauthorization does indeed seem to only show the untagged port information. Do a
show port egress ge.x.y which should tell you all the VLANs associated with that port.
Likewise show port vlan ge.x.y only tell you about the default (untagged ) VLAN.
show mac port ge.x.y should should you the MAC of both the phone and data device, unless of course they haven't talked or the bridging table timed out.
When I did a show mac port, I actually saw 3 entries for a phone plus data. The phone, for whatever reason popped up on both VLANs. I don't understand why
since the phone itself shouldn't be talking to that VLAN. You might try changing your set multiauth port numusers 2 to 3 just incase you are seeing the same thing and the switch is dumping the 3rd entry, which in my case was the VOIP VLAN.
James