If the frames were the exact same color which one would you keep (Peloton or Panasonic)? Don't trade a good frame for a more thrashed frame just because it's red. That's not a lateral move, that's a step down.
Let the friend buy the Peloton if he's in need and you keep your nice Panasonic.
The dent won't affect the ride. But, if you are gonna buy a bike with your hard-earned money, buy exactly what you want in the condition that you want. Don't settle. If you are concerned about the dent now, you will be concerned about it after you have done the deal and can't do anything about it.
Don't get hung up on NJS. I typed this post on a computer that was used to look at NJS bikes in Japan. For real.
Unless you have proof, anything someone says about a bike's pedigree is just hearsay. And even if it's true, what does it mean to you? I once owned a bike that was custom made for an Olympian. It was perfect for him...and sucked for me. I only kept it a couple of months.
Oh, and if the seatpost is supposed to be a 27.0, a 26.8mm seatpost will slip on the first small bump. They come in 0.2mm increments for a reason. I tried to use a 27.0 seatpost in the bike I just mentioned in the paragraph above which called for a 27.2...it never worked. It slid down even before I hit a bump.