yes sysnand is sigpatched, the fw img is only needed for rednand now.I don't think certain people quite understand how this all works and if they don't then they should not be using it cause the next question will be why is my wiiu not booting past the logo!
For anyone wanting to know, booting into systemnand is very different than using Coldboot-CFW & RedNAND fw.imgs, they have more sig patches than systemnand thats why you use them. I don't even think booting into systemnand on boot up menu will give you any sig patches at all, it should just be the same as systemnand as it was before I don't think its patched, tbh I have not tested it myself so I would not know I just presume its the same as booting into systemnand how it originally was.
Edit: sorry my bad, it is apparently from the op>"It offers a basic menu from which you can boot into the system menu which will get full signature and region patching." I'm not sure how he has achieved that I will have to test it. So are we saying then you only need a fw.img on your sd card for RedNAND? On mine I have set the lot up to use CFW-Coldboot img and RedNAND img booting from systemnand from a second ds vc title but it sounds like that is unnecessary.