Draco had meant it when he told Harry he wanted to help. There were a lot of things he wasn't suited for, but this at least was a way he could be useful. Besides, if the hardest part was going to be having lunch with his son while they brainstormed then Draco figured he was getting the better end of the deal.
He hadn't spent as much time with Scorpius as he'd wanted to. He'd been spending most evenings with Harry, and Scorpius was presumably spending them with Albus. So he was genuinely looking forward to this lunch. And if they didn't figure out a job right away then oh well, they would at least have spent some time together.
The house elves brought over a few sandwiches and some juice, and Draco set up the little table he'd conjured. There was a knock on the door and he opened it with a flick of his wand, grinning.