I didn't mean in the original timeline, actually...but it's clear that he IS there in the church and as he says, he's on his guard. He also says that he's going on even w/o Crono & Lucca...So, unless we're led to believe that Frog would have gotten his ass handed to him w/o the aid of Crono & Lucca (c'mon, you've gotta give him more credit than THAT)...I think it's fair to say that Frog would have saved Leene regardless, so that Marle getting Grandfather Paradox'd doesn't make as much sense as Lucca at first believed.