traderfag here anon, whats up?
Sorry cant help with that - options not my field, but dont think you can find that out anyway - options traded through brokers, and client info would be confidential anyway. Sometimes a hedge fund or other institution will let on they hold a big position, so you could try searching for relevant news stories, but doubt you'll find much unfortunately.
you'll often see speculation in financial media "who is holding the mega short in xyz" for example.