What knowledge did the Bishops of Salford have about Duggan?

Regarding the assertion by the Salford Diocese Safeguarding Coordinator, Father Barry O'Sullivan, that there is no evidence that Bishops of Salford had any knowledge of the complaints by children and their parents about Monsignor Thomas Duggan, please see

1. the comment posted by 'Anonymous' at http://www.blogger.com/comment.g?blogID=5504951114233652085&postID=1039836881192104623

Anonymous confirms that he and his father had alerted the future Bishop Geoffrey Burke to Duggan's behaviour during the 1950s

2. Paul Malpas' post at http://paulmalpas.com/ 'The Salford Diocese Examined'

Paul
a) recalls a telephone call from Father Barry O'Sullivan "on 8th October 2010 during which he explained ... how the Bishop, the Chair of St. Bede’s Governors, Monsignor Quinlan, the headmaster of St. Bede’s, Mr. Michael Barber, Michael Devlin, a solicitor and Chair of the Safeguarding Commission and O’Sullivan had met up in early October 2010 and discovered “serious and sensitive” evidence against Duggan that was too “serious and sensitive” to discuss over the telephone ..."

and

b) suggests, on the basis of testimonies received, that "the various bishops, including Bishop Vincent Marshall, Bishop George Andrew Beck and Bishop Thomas Holland ... had all received parental warnings and chose to cover it up" while "Bishops Kelly and Brain ... pushed this information to the furthest reaches of their files."