She knew she had to stall for as much time as possible. Fred was getting help. She just knew it. The more she could get Rodolphus to talk, the more likely he was to give any potential rescuers time to find them. As conceited and convinced of his own greatness as he was, she knew that Rodolphus would use any available opportunity to talk at great length about himself. He desperately needed the validation of others. No doubt it was rooted in some childhood trauma he could never quite get over. Maybe his cold, distant father loved his gardens too much and he was desperate to prove his greatness to the man who never had much use for his own children.