It's possible but not probable. JFK made his remarks in response to a speech Dulles had given to the CFR just 9 days earlier in the same city . The senator's comments were published in the Feb. '54 issue of a journal called the New Leader . Why would Kennedy repeating comments he'd made and published months earlier be "what was perhaps his first defining national moment"? DiEugenio claimed that the 2 statements represented "Kennedy's opposition to Operation Vulture" which he claimed "is simply absent from Dallek" but both appeared on the same page of one of the historian's books he was reviewing.
The ball is in DiEugenio's court, if JFK repeated the comment in the circumstances he claimed he should post his evidence here.