Roy Kerr's reply
1) I was in Austin Tx when the metric was discovered, not in the UK
2) Newmann was somewhere out East
3)I had never heard this story before, but it is complete nonsense.
Unfortunately, it is not possible. The reason that one can get as close as one off-diagonal term is a theorem by Achille Papapetrou. This requires that the metric be well-behaved on the axis of rotation. (Roy Kerr)