Warner is back in his home state of Western Australia ahead of Saturday's AFL clash with the Eagles at Optus Stadium.
The 24-year-old turned down significant offers from both West Coast and Fremantle before re-signing with the Swans last year on a deal that runs until 2027.
The Dockers might now struggle to fit Warner into their salary cap given their star-studded list, but the Eagles appear perfectly placed to launch another bid on the gun midfielder at the end of this season or next.
Making West Coast's case stronger is the fact their extensive rebuild is showing huge signs of coming good, especially on the back of wins over North Melbourne and Port Adelaide.
No.1 draft pick Willem Duursma, No.4 pick Cooper Duff-Tytler and fellow first-round pick Josh Lindsay appear destined for stardom, while other elite talent on their list includes Harley Reid, Jobe Shanahan, Archer Reid, Bo Allan and Reuben Ginbey to name a few.
Cox would love Warner to stay at Sydney long term, and is doing everything in his powers to ensure the 2024 All-Australian sees the Swans as his best fit rather than a club on the rise like West Coast.
"I don't really look at who's a destination club and who's not," Cox said in Perth before Swans training on Friday.
"I worry about do people want to come to our football club and do people want to stay at our football club?
"Mine's about trying to make sure that we can keep all our people happy and play the footy we want to play, which will, in turn, hopefully keep them there.
"We'll always speak to Chad about the possibility of staying and, first of all, just creating a team around him that he wants to be a part of."
Prized Swans recruit Charlie Curnow has kicked just five goals in three games this season, but Cox defended the former Blue.
"It's three games, my expectations are he plays a really strong four or five years at our football club," Cox said.
"When we got him, we knew it was going to take time to fit into a new team.
"I don't think you've seen too many key forwards around the competition -when they've gone to a new team - click straight away."
Sydney (2-1) welcome back Isaac Heeney for Saturday's match, while West Coast will be trying to plug the gaps left by midfield bulls Elliot Yeo (groin) and Deven Robertson (suspended).
