Thanks for all the responses and ideas!
So the research and journey has begun with Datawire. May it hopefully end in success. I shall inform you all again, whether or not I've become wiser.
To prove how fast such a typo happens, take my e-mail as example. The spamtrap domain in question is actually "
bluwein.ch" and not "
bluewein.ch". :-/
Datawire is off the hooks. Turning around the wheel and going North, towards the lands of Hetzner.