They all say that.

Maybe none of them are enlightened.

Maybe they are, but they see it differently from how we do.
Maybe they are aware that what WE think enlightenment is, is not actually what enlightenment is, so they want to ensure they don't unwittingly deceive or mislead us.

After all .. when asked what enlightenment is like, they almost all say, "It's like waking up. It cannot be put into words and you cannot understand what waking up is like until you yourself have woken up."

It doesn't really matter whether or not they are enlightened or not.

Spend some time around lamas, around bhantes .. you notice that they are onto something good that we are not yet. And the longer you practice Buddhism (assuming you are doing it properly .. hence the need for a teacher), the more YOU change in ways that are so terribly desirable and valuable to you.

So who cares is X, Y, or Z is enlightened? That's not what it's about. Buddhism works and THAT is what it's about.