The minimal install does not include NetworkManager-wifi. If you have the entire, as opposed to boot system, you can sometimes install it that way, off the DVD, though I’ve found that often, that doesn’t work, due to the DVD having outdated packages. The other solution is to temporarily hook up an ethernet connection, and then install NetworkManager-wifi through that. And yes, it does work during install. Personally, I think it’s a bad choice to have it work during install but not have the option to actually install it, but I doubt that RH cares about what I think.
If you can get it working from the install DVD, you will first need to install wpa_supplicant, iw, and and wireless-regdb.