I feel like he more characterised it as a casual acquaintance from high school. I'm sure they are privy to more information than we have, but whether that information is relevant is another story (as far as we know it's not relevant enough to get a search warrant). I have no doubt the family thinks and have thought since early on that he is responsible. I'm just not seeing any signs that LE shares this point of view, I feel like if they did there's more they could have done.
I'm thinking they have though that from day 1 since he was the last person to see her