Some sanctioning bodies will offer what amounts to an "at-large" bid to teams that they have observed playing.
That offer could go to a team that finishes out of the running for a bid in a qualifier, but is a solid team. It sounds like a state director might have been at the Westerville tournament and thinks that your team is deserving of a bid.
Also keep in mind that none of the sanctioning bodies are run by altruistic monks who just love to watch softball. Each is a business that has people to pay and money to make, and thus there is a need to have enought teams at the national tournament, since is it probably a primary money-making event.
Personally, I think that there are some good sanctioning bodies and some that are less oriented toward the love of softball and more focused on the money. I have traveled to a national event with a team that had fewer wins than you have fingers on one hand. So I am guessing we were there to help make the budget.
Still, if your team is willing, playing in a national event is exciting for the girls.