/usr/share/myspell/dicts/de-CH.dic is in hunspell-de-ch 20110609-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/myspell/dicts/../../hunspell/de_CH.dic
/usr/share/myspell/dicts/../../hunspell/de_CH.dic