nobody can, or will ever, point a finger at one person/organisation and clearly state 'this is the git who caused it to happen'.
One must always take a wider view with MoD as they always try to compartmentalise problems.
In this instance, try reading the PAC report into Chinook Mk3. It concludes that no individual or group can be blamed, but does say the main blame lies with "lack of management oversight".
List that "management".
Then do the same for Nimrod.
Compare.
Two names stand out in both. One (to my personal knowledge) was told in infinite detail what would happen on both programmes. Also, both were told of serious airworthiness shortcomings; both ruling in writing that aircraft need not be functionally safe when delivered to the Service. In February 1998.
May I suggest they should be first on any witness list at an inquiry.