Despite being signed until the end of 2025, the young gun half is struggling for playing time at the Red V.
Falling behind Talatau Amone in the queue to play in the key positions, Sullivan has had to settle for limited minutes off the bench, but even they have been limited by the signing of utility Moses Mbye.
Instead, he has been stuck mainly in the NSW Cup, although will play for the Dragons this weekend with Ben Hunt on Origin duty, away in the QLD Maroons camp as they chase a State of Origin series victory in Brisbane next Wednesday.
Earlier this year, Sullivan was involved in a shock potential player swap with Kyle Flanagan to the Canterbury Bulldogs.
While the move never materialised, Fox Sports are reporting the Bulldogs haven't totally given up on the idea of potentially having Sullivan join the club.
With Flanagan seemingly digging in and not wanting to leave Belmore, the idea of a player swap is off the table, although Canterbury's salary cap position - confirmed by Phil Gould - only has around $700,000 or $800,000 remaining for five spots in 2023.
Raymond Faitala-Mariner will take one of those spots, however, all of Matt Dorey, Matt Dufty, Zac Hetherington, Reece Hoffman, Tuipulotu Katoa, Joe Stimson, Jackson Topine and Brandon Wakeham are all still off-contract, with no signs any of them will be re-signed anytime soon.
The report suggests Ben Hunt could well re-sign at the Dragons beyond the end of 2023 as well, potentially further limiting the options of Sullivan if he can't get ahead of Amone in the pecking order.
Amone himself is off-contract at the end of 2023 and has been linked with a move to the Dolphins, however, regular first-grade minutes could keep him in the Red V, which could further tempt the Bulldogs to ask the question over Sullivan's future at the joint venture.