The Bad Arolson records often show where the person went after the war.  The majority of these records are found at the US Holocaust Museum but they are not online,  I've seen records that told the course of the destination request and date the person left for for their destination.  The Arolson archives is putting the collection online, but it is a work in progress. https://arolsen-archives.org/en/search-explore/search-online-archive/

IGRA has been indexing the incoming ship manifests.  https://genealogy.org.il/AID/

Immigration records for Palestine are held by the Central Zionist Archives which will tell you what records are available and how they can be accessed.

Ships arriving in Buenos Aires can be searched at https://cemla.com/buscador/ (site is in Spanish) this database includes ships through 1960.  Also often ships to South America went through New York, so check the Ellis Island database with destination of Argentina or Sud Amerika.