I rather think MLE should handle the interview with Goyle's boy.
It's a delicate matter, because he's quite young -- the same age as Draco, yes? -- so I would hope they'd send someone with an appropriate amount of subtlety. But delicately used, there are magical techniques that can enhance memory. Given that he's never used it, we need to know exactly when he last saw the journal, at least. If it went missing at Hogwarts that shortens the list of possible suspects rather significantly. Although there was an incident in the autumn, wasn't there? Was it ever established with any certainty who committed the break-in?
Private message to Lucius Malfoy
It's a delicate matter, because he's quite young -- the same age as Draco, yes? -- so I would hope they'd send someone with an appropriate amount of subtlety. But delicately used, there are magical techniques that can enhance memory. Given that he's never used it, we need to know exactly when he last saw the journal, at least. If it went missing at Hogwarts that shortens the list of possible suspects rather significantly. Although there was an incident in the autumn, wasn't there? Was it ever established with any certainty who committed the break-in?