We know visual and radar confirmation happened at the same time, so I don't know your point.
''At Andrews AFB, meanwhile, the control tower personnel were tracking on radar what some thought to be unknown objects, but others suspected, and in one instance were able to prove, were simply stars and meteors. However, Staff Sgt. Charles Davenport observed an orange-red light to the south; the light "would appear to stand still, then make an abrupt change in direction and altitude . . . this happened several times."[4] At one point both radar centers at National Airport and the radar at Andrews AFB were tracking an object hovering over a radio beacon. The object vanished in all three radar centers at the same time.[5] At 3 a.m., shortly before two jet fighters from Newcastle AFB in Delaware arrived over Washington, all of the objects vanished from the radar at National Airport. However, when the jets ran low on fuel and left, the objects returned, which convinced Barnes that "the UFOs were monitoring radio traffic and behaving accordingly." [6] The objects were last detected by radar at 5:30 a.m. Around sunrise, E.W. Chambers, a civilian radio engineer in Washington's suburbs, observed "five huge disks circling in a loose formation. They tilted upward and left on a steep ascent."''
This is all withing the same morning/night. The objects seen on radar and objects confirmed visually was also confirmed from the air and seen on the scopes. The fact it happened over a long period of time makes the event so unusual.