had there been a 3000m at the 1952 Olympics I think the finalists would have been:
Gaston Reiff (BEL), Gordon Pirie (GBR), Erik Ahldén (SWE), Ilmari Taipale (FIN), Väinö Koskela (FIN), Christopher Chataway (GBR), Fred Wilt (USA), Herbert Schade (FRG), Horace Ashenfelter (USA), Valter Nyström (SWE)
not so fast as these but good competitors would include John Landy (AUS), Curtis Stone (USA) and Evert Nyberg (SWE), and for an outside bet the French Junior 3000m champion Ben Ahmed Abdelkrim.
I agree with the assessment that Zátopek was not fast enough. he liked to race 3000m before a major race as a sharpener but broke 8:20 only a handful of times and went under 8:10 only once, at Brno in Aug 1947. 1952 is also a little too early for Vladimir Kuts who did not start to make a mark until the World Youth Games in Bucharest in Aug 1953; in 1952 he was only 6th in the Soviet 5000m championship running 14:55.6 behind Aleksandr Anufriyev.