A five day stay in Finland in ‘59 on his way to the USSR? He was waiting for the Soviet Visa.
The only connection to the assassination is that Oswald’s travel and stay in the USSR undoubtedly generated an extensive dossier in US intelligence.
So when they were looking for a useful idiot, he was an obvious choice. And his record of disloyalty removed any qualms about making him a patsy.
Makes sense. Also, if the Soviets were in on it, how’d they gt Jack Ruby to kill their man? Ruby was operating in far different circles than the Rooskies.