Among the mysteries that remain

Several of the mysteries that remain to be resolved are the name of Abraham van der Hulst's ship in the summer of 1652. Given that I have two lists of Amsterdam ships that claim to be comprehensive for 1652 and early 1653, the existence of an unknown mystery ship seems unlikely. Another mystery is why two ships involved in fishery protection, and which were taken by the English on 22 July 1652 are listed, but the Zwaan, listed in the Hollandsche Mercurius and other places is not shown. These other sources call the ship the Zwaan van Amsterdam, and the implication is that the ship was hired by the Admiralty of Amsterdam.