Here's my experience (but at Haneda - think it might be the same) about a year ago. Went to the lounge (JL first) since they didn't have sushi (like they do in NAR) and I didn't like the one sushi place in the secure area I asked if I could go out. It was a long layover and I wasn't fond of the meat heavy food in the lounge)
It took an escort person from the lounge to accompany me out (through some staff only type doors) so I could get to immigration).