Perfect, admirals are generally stronger than the Holy Knights. I’d say Shamrock is stronger than some admirals individually, maybe even stronger than Akainu himself. Kaidou, however, is superior individually to all of them—Holy Knights, admirals, and the Five Elders.
After all, if the admirals—who are all weaker than Kaidou—can somehow deal with the Holy Knights’ immortality and are therefore considered stronger, then Kaidou can do the same. That also settles Kaidou vs the Gorosei.