VinnieF,
Your post, while lengthy, is merely conjecture. Your figures are not grounded in reality, nor are your assumptions of how the money will be used.
Rhino horns do not go for $300,000. Also, the people the African poachers are able to sell the horns to will only pay the poachers a small amount. This amount will be sizable in relation to their poverty level, but nowhere near what they will be able to hawk it for in Asia. The amount of money they will get will be sizable only to them, not to the village. As such, the chiefs and local authorities understand the value of protecting the rhinos so that one or two can be hunted at tremendous value to the local people, not just to one poacher. By poaching, one is effectively stealing from one's village. This is most certainly not looked upon favorably by the local chiefs and authorities and is usually punished by death.
Last year two black rhinos were legally hunted in in Namibia, for  N$1,85 million and N$2,1 million, respectively. To put these numbers in perspective, the rhino that will sell tonight at auction may bring around N$10 million.
In 2013, 946 white rhinos were poached in South Africa. South Africa has the largest population of rhinos in the world, both white and black rhinos. Still, this is a small number and the number poached is far from sustainable. The reason that the number of rhinos poached has been growing from year to year recently is two-fold. One, South Africa (where there are more rhinos than anywhere else, remember), has been going through a financial crisis. The large landowners as well as government agencies have been forced to cut funding that went into the protection of the rhinos. Two, Asia has seen a huge economic upswing, especially at the top levels. This increased demand and greater prices, coupled with less protection and more desperation on the part of would-be poachers has led to a perfect storm of rhino poaching.
It is absolutely crucial that money for rhino conservation come from somewhere. As much as the average citizen and anti-hunters cry "boo-hoo," they are not donating to the problem. Should they even be expected to? There are many human rights issues out there - starving children all over the world as well as here in America, a lack of potable drinking water, multiple natural disasters - all of these are worthy causes for your dollars. Rhinos have to pay their own way. Hunters are rhino's greatest benefactors, just as hunters achieved such amazing results with the wild turkey, waterfowl, bighorn sheep, and so many other species. Without organizations such as the NWTF (National Wild Turkey Federation), Ducks Unlimited, and the Rocky Mountain Bighorn Society, much of our cherished wild game would be in dire straits.
VinnieF, your point about Africa being a hub of mismanaged money is not off base. I've spent a fair amount of time in Africa and have immersed myself in it through literature and following the local news feeds, as well as having kept in contact with those living there. Corruption is rampant. However, those in the rhino conservation effort have gone to great lengths to assure that the money donated to the cause goes directly with the cause. With this auction, which has gotten so much publicity, no politician or local official would dare touch the money for personal betterment. All of this publicity virtually assures that the money will be watched over by everyone.
There may be no perfect solution, to that I will agree. However, without trying, what do we have? Certain failure. The only shot that is sure to miss is the one not taken. These majestic creatures, which no one appreciates more than hunters, are in need of our help. Are you an organ donor? Once your body is used up, why not let it help those in need? This old black rhino is on the way out. It will do more to help the survival of its species than the thousands of people complaining about this auction.