After unlocking some of the doors at the basement of the Goldenrod Tunnel, I headed to where the director was taken and I spoke to him there. I obtained the Card Key from him that would unlock the doors at the Goldenrod City Radio Tower and then I climbed back up to the surface. I headed to the Pokemon Center to heal my Pokemon, then I wandered back into the Radio Tower. I unlocked the locked door that was blocking the staircase to the upper floors and I battled against Ariana. I headed to the observatory at last and I met Archer there. I defeated his Houndour, Houndoom and Koffing and he eventually gave up his plans to resurrect Team Rocket. I saved the game after speaking with the radio tower director.