6/19 UPDATE:
The Cubs have re-signed FA RHRP Tyler Duffey to a minor league contract.
Duffey opted out of his previous 2023 minor league contract on 6/1, but he apparently could not find a deal he liked once he got onto the open market. He likely has another opt-out (probably 8/1) in his new contract.
Duffey has been temporarily assigned to the ACL Cubs in Mesa while he gets himself back into game shape. However, by rule a player with his service time cannot remain on an ACL roster after June 30th.