You mean the aim is to release the floater again that he can fulfil his journey (like he did in my solution)?
Or to release the floater after all is said and done, i.e. just to get another lemming saved?
In any case, I'd want to check what can be done.
As for Final Call, I've got a couple of solutions that barely fail. I'll check whether I can indeed do it using a floater, and in case that works, I'll send you that demo. No hints please, though.