CCM does the right thing. The profile under /var/lib/ccm has the correct unicode string
ncm-ncd --co metaconfig writes out the file in latin1 encoding. Doing iconv -f latin1 -t utf-8 gives me a valid unicode file that is accepted by the program.
Putting a LANG and LC_ALL variable to en_US.UTF-8 in ncm-ncd doesn't change a thing.
So I think that only thing needed is a way to set the binmode thingie to unicode.
See https://github.com/quattor/configuration-modules-core/issues/1494, best start reading at the bottom: