The Dolphins have already been linked with several players since being granted the NRL's 17th team licence and O'Sullivan will only boost their ability bring in strong talent.
The recruitment guru's departure could also have an impact on the Warriors, especially for prop Matt Lodge who is O'Sullivan's son-in-law.
Lodge has an option in his Warriors deal to leave in 2023, which means he will be free to negotiate with rival clubs from November 1, according to the Courier Mail.
Lodge is also close to Bennett, who he credits as helping save his career during his time at the Broncos, while having ties with Redcliffe – where the Dolphins are based.
The Warriors, meanwhile, are reportedly preparing big money bids for Sydney Roosters star Joey Manu and Parramatta lock Marata Niukore.
However, Manu could now become a target for the Dolphins, with O'Sullivan reportedly having a high regard for the Roosters star.