Well my opinion it should be an official NFOA event, and we be partnered with the other organization which has insurance. Why, first we would want it to be able to raise as much money for the NFOA as possible. To do so it is much easier to get sponsors who provide swag for competitors, nice prizes, and even put forth money to support and underwrite the event if the "Organizer" and beneficiary are an organization like the NFOA. You could get a company like Cabela's (this is an example, I have no inside info on if or what they may do) to donate something to put into swag bags, possibly a prize of some sort and throw some money at the event to help with costs, then you get another sponsor who furnishes targets and a couple dollars. In the end these couple dollars add up, and if you work it right you get the materials needed donated by the sponsors so costs are covered and the entry fees are also income. Yes the first year of and event like this may have very limited income, but if you do it well future shoots will draw more Sponsor support and with it more income as well as better prizes and swag bags for competitors.
Now how does it fit the Mission, Goals and Vision? Well it raises the profile of the NFOA amongst shooters, possibly bring positive press, all of which will help draw new members. And along the way we can hope to raise some money, which even though there is nothing in our Mission about raising money it is needed for the organization to operate. Sometimes you need to do things because just overall they can help the organization grow, even if it's not specifically covered in the Mission, Goals, and Vision.