The problem isn't a shortage of proofreaders, FWIW.
This might seem a little bit harsh, but if it isn't a shortage of manpower it's a shortage of quality work.
There is a reason why proofreaders work in certain ways, it's because of the "can't see the forest for the trees" effect that authors get. It's really hard to proofread your own writing because your brain just overlooks stuff it "knows" to be fine.
If you're telling me that the authors were not in charge of proofreading their own work and that an entire team that did not take part in the writing allowed SR5 and R&G to be released in the state that they have been released, something is going fucking wrong over there that we are begging you to let us help you fix for free.
Do not get me wrong. I love SR5. I think R&G has a ton of great ideas and is like all of the ingredients of a delicious cake that were poured into a good looking frosting shell and then baked for 7/10th the required time. Then, when the hungry fans cut into the mostly-baked mess and go "what the fuck this isn't finished yet" it is really really hard for said fans to tell their friends "SR5 is awesome, I love it, buy the book right now". Instead, we have to make excuses like "SR5 is going to be awesome, I really like where it's going and hopefully most of the stuff that's wrong will get sorted out."
Now the problem is that as I'm sitting here, I've heard no news about SR5 getting re-released with the updates in it (which really change certain core rules quite a bit). And woe to the poor fuckers who bought the physical SR5, they're hosed forever unless you're sending them free new books. "Oh, we made a bunch of typos" is totally acceptable for errata. "Oh, everyone pointed out that this set of recoil rules doesn't work as intended so we changed them" is a problem with releasing a product before it is finished.
Now take the fact that R&G introduces a TON of complex new shit and NONE of the complex new shit is actually finished and we have a big fucking mess on our hands, chummers, that COULD HAVE BEEN AVOIDED if you had released the full text of R&G to the fans here on the forums for proofreading. We would have LOVED to save you the embarrassment and the discredit of releasing a book that's all fucked up. We love Shadowrun, we want to do everything in our power to make it the best it can possibly be.
Please, for fuck's sake, let us help you.
If you honestly believe that nobody would buy the books if you released the beta first, you are straight up motherfucking wrong and being wrong in this instance is fucking up Shadowrun. As it stands everyone is stealing the pdfs all over the internet anyway, so stand the fuck up, ask for the help that you need from the fans who want to help you, and release an acceptable product. We've loved Shadowrun for a long, long time. We want you to do it justice. Stop being pigheaded, it's 2014, crowdsource the shit you need to crowdsource.