I have no advice to offer on this, but I hope someone else does -- because I have faced the same issue in the past and didn't know what to do about it.

I would definitely plant it as it is. I know of no good that would come of further division. Keep soil watered as you normally would.

Don't divide. A rhizome piece like this is already on the brink of death; all my rhizome pieces that have no leaf attached died eventually. Further diving it would only reduce its vigor. Good luck!