Even just planning to remove all of the melted fuel is a long way away.
I can't remember if they were talking about Unit 1 or Unit 2, but from what I understood is that due the collapsed rubble above/around the reactor, they only have a very narrow opening, which means they've struggled to use larger robots.
And I believe the robot operating centre is a bit of a distance away from the reactors too (probably so that the robot operators don't need to wear protective equipment).
> What they need is a sort of "anteater-tongue machine" that just will try each crevice until finding the correct path.
I think the problem is that once you get through all the debris, there's a big cavern. Hence why they're using some sort of crane robot on a rope (it reminds me a bit of a [claw machine game][1]).