The comment made above regading BA or CX management reaction in a similar situation by sacking those involved I think would be highly unlikely. Having worked for BA for 32 years, my impression is that if those involved were prepared to be as constructive as possible in the investigation, they would lose large chunks of seniority and the Captain his command for a period. The culture was very much one of expecting you to admit to your infallibility and assisting in the prevention of a similar situation in the future. BALPA was very much involved in such serious investigations, one of its more useful functions in it's BA directed activities.
Having said that, as someone else pointed out, there had to have been a massive loss of SA by all three pilots for the various glaring warning signs to have gone unnoticed.