Gigabelly.............
If it's knowledge that you want, then most all NRA courses would be of marginal value to you. This comment is based upon your own statement of your own firearms experience. You most likely don't need for someone to explain the Three Safety Rules and point out handgun parts on a chart.
If it's credentials that you want, then you need to identify those specific credentials and enroll in classes which will provide them to you. You'll have to endure some very basic, repetitive information, because that's what NRA classes typically provide.
If--for example--you want an NRA RSO credential, NRA provides a couple of paths thereto. You can check those out on the NRA website. You might be better of with an IDPA RO credential, which is listed elsewhere on the NFOA Forum [contact jthhapkido in that regard].
If you want an NRA RSO class and are willing to work to help build a critical mass of say, 5-10 attendees, then pm me on that issue.
If you want a metallic cartridge reloading class, I'm offering one tonight in Papillion that's already filled, but may offer more in the future, depending on interest. You can likewise pm me if interested.
You also might want to check out those classes offered by Signal88, Chris Zeeb, Shawn Whittington, and jthhapkido. They are more focused on good, solid knowledge than credentialing, but they are all worth the money and time.
Good luck otherwise in your quest.