The woman, believed to be Lithuanian, was struck by a car on the A38 near Burton-upon-Trent around 20:30 BST on 6 July after leaving the man's vehicle.
Johnathon Allison, of Colman Street, Hull, has also been arrested on suspicion of murder.
Mr Allison was remanded in custody at Cannock Magistrates' Court on 8 July.
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Staffordshire Police said Mr Allison has been released under investigation in connection with the murder probe.
He will next appear at Stafford Crown Court on 11 August.
Police said the woman left the vehicle as it pulled into a layby, and was hit at "high speed" by an oncoming car.
She was airlifted to hospital in cardiac arrest with head, chest and pelvic injuries, but later died.
Police are now working with authorities in Lithuania to confirm the identity of the woman.
A man has appeared in court charged with breaching a restraining order following the death of a woman on a dual carriageway.