The signal comes OFF pin 9 and goes TO pin 3, not the other way around, as seems to be implied by all the information I was able to find. Or at least for an original NTSC NES it does. So if you want to get the VRC6 channels out to their own RCA out, you need to connect pin 9 to that, not pin 3.
Sorry if someone already posted this, but I couldn't find it, and this could've saved me like 20 minutes of "why isn't this working?" the other day.