Hi Jan,
Did you ever get anywhere on this? Asking because my 3xgt grandmother's brother Peter Ludwell was William's "victim" and her husband (my 3xgt-grandfather) John Nicholls the main witness.
I've found a news article dated 4 February 1837 saying he was given clemency by the King, so things moved pretty fast!
Would be interested to know more if you've found anything?
Best wishes,
Sarah
Wellington, NZ