Did you check out either death mentioned on the previous thread to see if they were yours?
I seem to remember having a stab at this one after your previous post, but not found anything concrete. Since Knight is such a common name

I thought I would look at Rachel and her origins to see if there might be clues there.
There is only one Crisdee baptsism in Havant. I can't find a Crisdee marriage for William & Rachel (Rachel's parents) or any burials for the couple

Have you looked at any marriages of the children of William & Rachel Knight to see if William is noted as deceased or note? I realise it's no guarantee but it might help.
Any wills? Was William apprenticed to anyone?
Nell