VAG COM 409-1 (though I did try an earlier version as well to no avail). The test results are for Com 3:

Port status: OK
Interface: found!
Type: Serial/Pass through
Opto/Iso: Yes
Ross-Tech Design: No

The cable is just a third-party cable that a friend is no longer using (he swears it worked on his VW). Once I get this working I'm going to buy the software and probably the kit as well.

THANKS!!