Max level for Lull/Soothe/Calm
 

The Wiki says that the max level that This line of spells can land on is 55, but I have landed Pacify on a level 58 Cliff Golem that was Tashed. Is the Wiki wrong?

Yes
I have landed pacify on Korocust,lvl 59 mob. It took a lot of casts
I have also pacid cliff golems to confirm your experience.
I havent attempted a lvl 60 mob yet. I have tried to pacify queen dizok,she did not like that very much