Lajos Gyorgy Kvalka, 48, surrendered to Tourist Police on Samui and was brought back to Phuket where the killing of Peter Reisz, 47, allegedly took place at a house in Phanason Residence, close to Central Festival Phuket.
Mr Kvalka says he was at the house on November 24 when a third Hungarian, Moshe David, 38, killed Mr Reisz, beating and stabbing him to death.
He says he took no part in the killing but was a witness.
Today's reenactment was expected to include a trip from the Phuket City house to jungle near Patong Hill, where Mr Reisz's body was dumped.
Mr Kvalka may have been the driver and could have helped Mr David place the body in the vehicle and carry it out.
He surrendered on Samui as the net closed around him following the discovery of Mr Reisz's four-wheel drive vehicle for sale for 500,000 baht on Samui.
It is believed Mr Kvalka took possession of the vehicle after the murder.
Mr David, whose name has been connected with at least one other disappearance of a prominent Hungarian in Thailand, is now in Phuket prison awaiting trial.
He and Mr Reisz fell out when Mr Reisz forged papers connected with a Samui property. Mr Reisz also told Samui police that Mr David was in possession of an illegal gun.
Mr David tracked Mr Reisz to Phuket where he has confessed to killing him. Mr David has already carried out a reenactment of the murder.