Here are the possible solutions for what the theme answers are in or what they contain clue
Answer
Clue
Relevancy
order
Clue
What the theme answers are in, or what they contain
Definition
to give a command to
gelinserts
Clue
Shoe additions, and what this puzzle's theme answers contain
insideinfo
Clue
Secret the theme answers contain
subliminalads
Clue
What this puzzle's theme answers contain (if you look closely enough)
rockbottom
Clue
With 133, the name of the band whose members appear in the theme answers. (They disbanded in 2012 after raising millions for literacy, but they're reuniting this weekend for one last concert.)