True, but as stated, he might have requested time off to work on other projects.
Maybe they need to write a nude scene with him and Sawyer? Maybe Kate could catch him with Sawyer doing Some au natural fishing?
Kate walks along the beach and is startled to see Charlie & Sawyer bare ass naked while fishing.
Sawyer: "Hey freckles. Wanna join us and make it co-ed fishing?"
Charlie: "Yeah Kate. We are embracing our freedom from society and living free like in the garden of Eden"
Kate: "Um, no thanks. You two can keep bragging about your tackle alone."