All 3 Citadel companies belong to Ken Griffin/are related and are unlikely to have meaningful short positions..
The company that is Robinhood's customer and pays for order flow is Citadel Securities, which is the market maker and is definitely not short GME.
Citadel (hedge fund), is not short GME as they generally sell boring complicated solutions to rich people (fixed income, insurance, hedges etc). They do invest into other funds (like Melvin Capital), which may give them indirect exposure to the shorts.
Citadel technologies, sells their tech.
