61.55 does not apply to any King Airs because an SIC is not required. The 90's, 100's, and 200's are below 12,500 lbs. If you have a multi-engine license you are good to go.

Am I missing something?

Now would I get the high altitude endorsement? Sure. But that is 61.31. Have I given training to people in King Airs and left the PIC column blank when I signed the log book even though they were sole manipulators? Yes. That doesn't change the legality or the ability to log the time.