Ok 1. Theres no plan he could have made to get luffy out of that situation, 2. An entire fleet was shooting at Sanji and Sanji got hit once, and even then he didnt even know he was shot until chopper told him in the next chapter. 3. Sanji couldnt have gotten out of that yonko fleet situation by himself, If your really a fan of sanji you should know Holding Luffy is a literal nerf to sanji fighting style. He uses both hands to take out large groups.
Lastly it was Yonko fleet and Oven was one of the guys in the fleet. Oven alone is enough to make it a difficult fight for Sanji. 1 person shouldnt have been able to escape from a yonko fleet. The Germa being there was absolutely necessary......
The context of Sanji vs King is different from the fights you mentioned, Doffy and Vergo were the main villains/antagonist. King in the context of this arc is an underling of a Yonko he's not the main arc villain/antagonist.Sanji getting overpowered makes sense, based on luffys portrayal against katakuri. King would get the better of most people in that situation. Sanji is fighting someone much stronger than him, a struggle should be expected honestly. The good thing about this arc is that it requires Sanji to fight unlike those arcs you mentioned. So there may be more to sanji vs king. We'll know next chapter. Its honestly a feat that Sanjis able to clash with the guy and save momo honestly. Considering Katakuri whooped luffys ass nonstop.