Fridge Horror: When Cooper first walks into Club Vandersexx, the Dominatrix immediately acknowledges that he's American. If she's well aware that he's an American, she must have known that he wouldn't be able to pronounce the safeword that she wrote down. And as pointed out above, the safeword is written in some weird Scandinavian tongue that isn't even spoken in Amsterdam. So when she does the whole "session" with him, she's not providing the usual services that she would to a customer... she's just torturing Cooper for the hell of it and taunting him with the fact that he can't make her stop.
Not exactly fridge here, since her expression gives off that she's clearly indulging in & enjoying torturing the ignorant American.
All dommes enjoy causing pain to some extent, but they usually set limits and make sure that it's safe and consensual first.
There is little evidence to support that she's a professional domme, as opposed to just the operator of a scam house. The locals probably know to stray away from Vandersexxx, whereas any tourists, wouldn't. The safe word is not only not pronounceable to an American; it's just not pronounceable.
Fridge Logic: Was there something stopping Scotty from setting up a new email address and saying he was drunk?
Clearly the movie is set in a world where a person has only one email address, given at birth, and can't even use it to pass on a message from someone else. Or Mieke is blocking all mail from unknown senders. Or Scotty is just that stupid (his love for gimmicky GIFs and ditto email programs as well as using a paper dictionary does suggest he's rather tech unsavvy).
I thought that but in a re-watch I got the impression that Mieke blocked her own address.