That's why I want to have Vault 112 in the Mojave, so that when you search for your daddy you have to travel there. What then happens until you get shot in the head can either be headcannon or explained through further modding, I'd think. But the base would be there, just by moving the Vault. "The first conversation with Veronica will be a bit weird" Not just a bit, imo. Since you have no way to roleplay that through dialogue or quests, you'd have to do the lion's share of the lore as headcanon. Far from ideal, I'd say. I agree that what you propose would work nicely as a motivation but would also require heavy modding to make it even remotely seamless. Edit: Unless ofcourse, getting shot in the head makes you forget all about DC, being a Knight and so on. That would work, I guess. But then there are way too few dialogue options about not knowing your past (to me).