I found that if I skipped all of the asterisks and just go straight into the changing room, then she will not discover the shopkeeper behind the mirror!
Okay, just tried it and you're right.
But I find it totally illogical to go into the changing room without clothes and then admire yourself. She could do that every morning in the hotel.
Here it would be more logical to choose a new piece of clothing and then put on a show in front of the mirror, especially since there are also different statements about the pieces of clothing. (looks good, I already have it, etc.)
But I don't think that will be changed yet.