In the Goblet of Fire we see Arthur talk about how Amos works with him at the Ministry. Does this mean that he works in the Misuse of Muggle Artifacts office as well?
It's not mentioned in the film, but in the source novel we learn that he works for the Department for the Regulation and Control of Magical Creatures.
Mr Weasley was shaking hands with a ruddy-faced wizard with a scrubby brown beard, who was holding a mouldy-looking old boot in his other hand.
‘This is Amos Diggory, everyone,’ said Mr Weasley. ‘Works for the Department for the Regulation and Control of Magical Creatures. And I think you know his son, Cedric?’
Harry Potter and the Goblet of Fire