Probably unsure of what can or can't be said without giving away spoilers. Although after taking a glance over the interview itself as opposed to the out of context quotes you provided, it seems to me that "I think" was just said as a natural conversational tool. People say "I think" all the time in daily conversation, even if saying something they are certain about.
But, you know, continue yelling at the clouds.
God forbid I ever get interviewed about anything serious in life and all people can see is a transcript of it, because I can stumble big-time in front of the camera.
"I think, you know, I do believe in climate change, yeah, uh, huh."
BREAKING: QUINTON, AN IDIOT, IS A CLIMATE CHANGE DENIER.