Taking the books, and comics into effect the Federation had access to many friendly Klingons before 2293; Konom who served on the Enterprise, Bernie the half Human/Klingon; Dr G'dath an exiled scientist who helped Kirk in 2271; Maltz who was captured over Genesis; plus undoubtedly a ton more- so wasn't it odd Dr McCoy didn't know enough Klingon anatomy to save Chancellor Gorkon?