The other star core slots are on that smaller console right behind the power armor display. If you do the Hubologist quest, you'll come across a star core... At the northeast corner of the map, you'll find a town called Bradberton and just south of that a Red Rocket which is now your new settlement. There's no star core in the Bottling plant, but you'll want to check out Project Cobalt. It's behind that locked door with dead Gunners. To get there, if you re-watch the video, at 48:35, go straight instead of turning right. Once at the control room, turn right to a flight of stairs going down to the bottling area. When you take the Nuka-Galaxy ride, you'll find that the robots have re-spawned. Don't mind them, they won't be hostile. Enjoy the ride...
