Volume IV is translated by John Minford. Not David Hawkes who translated Volume I to III.
This Volume clearly identified Gao E as the editor for chapters 81 to 120. Gao E is a Chinese literati whose highest achievement is to become a minor official in Peking.
It is strange why Penguin omitted Cheng Wei Yuan as a co-editor with Gao E. This is because this Volume reproduces from the 1871 printed edition of the complete 120 chapters a Preface each from them and a Joint Foreword from both. In his Preface, Cheng clearly said ” with the help of a friend, I carefully edited the material…”