You clearly didn't read what I said.
3.0.0U The last number 0 means he doesn't have a working browser so he can't access the kernel exploit that way, if he tries to open the web browser it will ask to update first, cart based updates don't upgrade the browser neither, so if he uses let's say Smash Bros to update, he will be in 8.1.0 with no mset and browser.
Why do you think N3DS users in 8.1.0J are screwed up from using CFW.
There is been some really rare reports of 2DS with no browser out of the box too, 0 as last digit again.