well there is a thing that you need to have beaten at least pryce and jasmine that the rockets appear there.thanks for that sorry to be a newb and ask so many q's but i cant battle the team rocket director at the radio tower and i've beaten the previous team rocket attack in lavender town so what do i need to do coz i beat them at slowpokes well as well
if they're there you can go to upper floor to battle the fake director who gives you basement key.
the basement is in goldenrod where you can find the real director who gives you card key which you can use to access to the another part inside radio tower.