It could be anyone, even Kate. After filming, while the girls were hanging out, something that could've easily slid during filming, could've become grating. Which probably would've stuck out in KL's mind during the interview and what should've been a kneejerk comment is getting more press 'cause it's revealing stuff about the show. Who knows...

This is just the realist in me, ultimately I'm with you because I'm nosey as hell.