Thank you for your question. I am the designer of the Science Buddies wind tunnel that you linked in your question.
The tunnel was designed to test airfoil models, and so I do not believe it would be appropriate to use it for testing golf balls. However, if you were to modify the design a bit, you may be able to get what you need out of it. Unfortunately, I cannot offer expert advice about testing golf balls in a wind tunnel.
I suggest that you re-post this question in the Physical Sciences forum for grades 9-12. There are many more experts there that can help you adjust the design of this tunnel, or come up with other ideas, in order to test the golf balls. The link to the forum you want is here:viewforum.php?f=29
Good luck on your project!