Just my 2d worth ...
but the fact that Gray seems to be the only one to have a) recognised that there is a problem, and b) owned up to having some responsibility means, IMHO, that he is the sort of person that we should be keeping. OK, it's reasonable that he shouldn't profit, and should more likely suffer some token personal loss, but here is someone who's exhibited both knowledge and ethics yet he is 'let go' !
The ones we REALLY should be after are the ones who are culpable but are trying to pass the blame onto others. These people, and I believe this goes right to the very top Gordon, have shown a lack of skills and a lack of ethics - both of which should be enough to have them booted out with prejudice.
But this is UK politics - rather get rid of the scapegoat than the people to blame !