It sounds like he/she is already in Bangkok. In that case, I would just do the BKK-NRT flight. This is a long itinerary and you may not want to add indiscriminate segments. I recently did the same thing and it worked out well. The JL lounge in BKK isn't anything extraordinary, but it's a nice place to kill a bit of time.

Looks from what you are saying that you want to stop in Cairo, Bangkok, and Tokyo. If this is correct, with a little different planning, you would be able to drop this into the ow130c category.