I'm about to order the parts as you describe, by inner piece you mean the hanger right and by outer piece you mean the nut?
So inner piece or hanger from the first link and the complete set including the nut from the second link with the 1.5 threading, is that correct?
The hanger is two pieces, which I describe as inner and outer. The inner piece is always the actual “hanger” piece that connects to the derailleur. The inner and outer pieces sandwich the frame if that makes sense. The stock derailleur hanger set has the threads on the inner piece with the actual hanger part. The stock outer piece is just a piece of metal that is secured to the frame with a tiny bolt. I didn’t like that because if that tiny little bolt fails (and I’ve had it happen) then the outer piece falls off, which means the frame dropout isn’t secure. The thru axle will keep the wheel in place secured to the hanger, the frame won’t have any attachment points. So the frame is really only secured with the tiny bolt.
With the Cube hanger set, the threads are moved to the outer piece. So now you get the inner piece with the hanger, then the frame, then the outer piece with the threads. So now the thru axle connects to the outer piece and secures everything. Much more secure.
So what I bought is the inner piece (hanger with no threads) and a separate outer piece (with threads) and combined them to get the set.
Hope that makes sense.