Academy Manufactor's replacement effect applies to creating a token copy of any of those creatures being created, and instead of getting a copy of that creature, you will create a Clue, a Food, and a Treasure token each, none of which being any more than the basic version of that token.
Academy Manufactor's ability is a replacement effect, which roughly means "if something would happen, it doesn't happen, and something else happens instead".
This really is a better explanation than any rules quote would give in my opinion, however if you want to read further, there's this excellent page on magicjudges.org on the topic, and of course for completeness's sake, a relevant rules quote:
614.6. If an event is replaced, it never happens. A modified event occurs instead, which may in turn trigger abilities.
Two conditions need to be true for the same permanent in order for Academy Manufactor's ability to apply:
- the permanent needs to be a token
- the permanent needs to have the Clue, Food, or Treasure artifact type
Both happen to be true for the creatures mentioned, so this perhaps unusual interaction happens.