I know it sucks to derail your plans, because a new puppy is something to be incredibly excited about. But you will be excited, no matter when your puppy arrives, and more importantly, you would have the life-long assurance of a good breeder and the knowledge that you did the right thing if you go with an ethical breeder.
I also understand the conflict about wondering if you don't buy her dog, maybe the next person who is not as well prepared and not as loving will screw it up. I don't know if this article answers any questions, but it might be a start.
When I was searching online for more information that I could offer you about this breeder, I came across a public announcement from Shemax (Sheila Maxwell) that said, "WE ARE GOING TO SELL OUR BASENJIS TO CANDYCE WITTE OF CALDWELL, TX. SHE'LL FURNISH YOU WITH THE SAME PUPPIES AND SERVICE THAT WE WOULD WE ARE HAVING TO QUIT DUE TO HEALTH REASONS" (apologies for the caps – I just cut and pasted). The name rung a bell with me as several forum members have had negative experiences with that breeder's practices in the past. So if this breeder provides the "same puppies and service," that's not exactly something to hold in high regard...
My main concern is that you can't verify ANYthing she says about her breeding practices with your own eyes. I've heard of plenty of breeders who insist that their dogs are "loved" and "happy" and "play every day," yet they spend their entire lives in an outdoor kennel, their frantic barking and wagging tails whenever a person walks by is interpreted as happiness when it's actually a desperate plea for the human companionship they DON'T get, and the amount of "play" that they get in a day amounts to being stuck in a 20' x 30' pen in the back of the farm, where they are left for hours where they MIGHT get some human interaction, and then returned to their cages at night.
I say this as someone who bought my first dog (my Shiba, who is now nearing seven years old) from a totally shady seller. My Shiba was pretty sharp-tempered, we made a lot of mistakes in his puppyhood that we might have avoided with the guidance of a more knowledgeable breeder, and his health was excellent until he was about three years old. Then his allergies started getting worse and worse every year, until two summers ago when he was diagnosed as hypothyroid, a condition which is strongly influenced by genetics. Like Holly, I love my handsome pup who came from a for-profit breeder. But I would never, ever allow myself to do that again, because this ONE time, I got lucky.
If I were you, I would definitely hold off on a decision until I had done more research, including a thorough reading of the BCOA website because there's a lot of useful information there. Check out this thorough section on screening breeders, for example.
Doesn't have to be all serious reading – there are tons of gorgeous pictures of Basenjis that will get you through it, too. ;)
(Sorry so long...)