She was never going to reply, and it was not the subject line.
Attention modelled on how buyers actually read cold email: hard drop at the first sentence about you, and it does not recover. She never reached the ask.
"We help 3PLs cut pick errors and get more out of the same warehouse footprint, and we work with a lot of operators at your size."
That is a sentence about your product and your customer list. She has no reason to care about either yet. Everything after it reads as a pitch, so the ask at the bottom lands on someone who has already stopped.
You did the homework. Opening on Rotterdam and four sites is a real, checkable fact about her world. Most people open with a compliment or a stat. Nine words in, you had earned the second sentence.
A problem she would recognise. Nowhere does the email say what is going wrong for her. Pick errors are your category, not her complaint. Without that, there is nothing for her to agree with, so there is nothing to reply to.
You will keep getting the reply rate you are getting, and you will read it as a list problem. It is not a list problem. Halvard is a good account, she is the right person, and the fifth site she mentioned is the opening you already found and walked past.