What knows a LN intermediate node about a transaction?

Following with How much privacy does Lightning actually have? there is some extra questions I would like to ask.

Suppose that Alice send a LN payment to Bob and the transaction founds a route with three jumps on intermediate nodes C, D and E:

Alice -> C -> D -> E -> Bob

• Can C know that Alice is the original source of the transaction, can he infer that inspecting the package it receives?
• Do D knows about Alice and Bob?
• Can E know that Bob is the final destination?
• Does it depends on some of the channels being private?
• Can a bad actor that controls both C and E knows that the transaction is the same?