How do we know that Fredo didn't hang out with or meet Ola in Nevada? At the nightclub in Havana, Fredo obviously lied when he said he and Ola never met. Later, in the boathouse, he admitted that "Johnny Ola bumped into me in Beverly Hills..." That may have been true for the purpose of that meeting ("He said you were being tough on negotiations..."). But it still doesn't preclude their having met in Nevada.