That's them 
That's right but I would say that he is not your William. The child Ann marries as Ann Waterhouse - she was born before the 1841 marriage.
Why do you and your friend think that the 1851 death is him?
Would you not consider this death?
March quarter 1849 William Shackleton Keighley volume 23 page 287
Burial Keighley March 17th 1849 abode Branch House, Newsholme.
The death ties in with Rose being a widow. It might not be him but it is a better fit.