It's not that he wasn't paying attention.
It's that he wasn't there at all
http://www.giantitp.com/comics/oots0279.html
him running away from Miko while the Order is getting exposition
http://www.giantitp.com/comics/oots0277.html -- you'll notice he's not here.
Celia even points out that he's not there for the trial, in which the exposition takes place here: http://www.giantitp.com/comics/oots0269.html
(yeah, sorry, kept finding more strips)