"Steal magic?" Ollivander huffed again, but this time louder. "Listen, lad. I've been in the wand business my entire life, and I assure you that not only is the possibility of a wizard stealing magic from another impossible, it's complete bullroar! They tried to push this sort of propaganda on us before." By 'they', Ollivander was referring to Pure Blood Supremacists and by 'before', he meant the 1970's, during the first wave of Voldemort's terrorism. "You can't steal magic, just like you are unable to steal another's eye color or height! I'll have you note, that in our interview, I made no such inquiry into your parentage. My own Mother was a Muggle-born, for Merlin's sake!"
This whole topic really set Ollivander up in arms, and it showed. Dennis' question had him laughing, however. "Of course you may still work here! I intend to have you begin straight away!"
Ollivander considered the wand Dennis had handed over. "As for this... since it's ill suited for you, I'm perfectly willing to hold on to it, if that is what you desire. However, it's my opinion as a wizard that better to have an ill suited wand than none at all. You're welcome to continue using it, if you'd like. As for making you a new wand..."
It seemed as though Ollivander went into a little trance, staring at Dennis in such a way that it looked like he was searching into his soul. "Yes... yes, indeed. Hrm. Well. I haven't made a custom wand in a long while, because it rather goes against my philosophy of the 'Wand chooses the Wizard', but since we don't have that luxury here in the village... stand up."
Once Dennis was on his feet, Ollivander pulled from his pocket a tape measure... it had been on his person when he'd went to Hogwarts, for he never left the shop without it. Just like he'd done the first time Dennis came to the shop, Ollivander began measuring parts of Dennis' anatomy, taking mental notes and muttering to himself. When he was finished, he announced, "It most definitely can be done." He put the tape measure back in his pocket. "I've been pairing wands with witches and wizards for an awfully long while, so I'm a pretty good judge of character. Plus, we have your old wand's characteristics to go by as an additional gauge. I'll select the wood and the core, and once you have the proper training, you may begin working on crafting your very own wand. We shall do it together!"
Ollivander was elated by the prospect: not only was he back in his familiar habitat of making wands, but he wanted to do this for Dennis as proof positive that all this nonsense the Death Eaters fed him was wrong.