Benchmarking for an unlisted involves some discretion since the whole point is that there is no existing code. If there is an equivalent open procedure, that is what I benchmark. If I feel due to the particular circumstances documented that this case was a little more complex than the open, in my appeal letter I will specify why and ask for 120% of the open benchmark code.
The 3 codes you are considering:
38564 Limited lymphadenectomy for staging (separate procedure); retroperitoneal (aortic and/or splenic)
38747 Abdominal lymphadenectomy, regional, including celiac, gastric, portal, peripancreatic, with or without para-aortic and vena caval nodes (List separately in addition to code for primary procedure)
38780 Retroperitoneal transabdominal lymphadenectomy, extensive, including pelvic, aortic, and renal nodes (separate procedure)
I don't see how 38747 or 38780 could even be close when it was 7 para-aortic nodes, which would leave 38564.
PS - I work in gynonc, not urology, but I don't think I've ever seen pelvic laparoscopic surgery where they removed para-aortic but not pelvic. Of course the kidneys are higher up than the uterus, so that could be why. To me, another possible option would 38572-52 since no pelvic nodes.
Hope some of that helps.