Horton

[Sternjaeger II]

maybe, again there's no certainty, you need to bear in mind that the primary need was structural flexibility and resistance to high G-loads, so the use of carbon layers was probably meant to address that more than radar stealth.

This is something that could be also verified in the RLM specs for the project, I doubt the Horten brothers would have bothered to come out with an idea on a field they probably didn't have a lot of info about(radar technology), especially because it was under strict secrecy at the time.