I have to say, I don't think you did make it as neutral as possible. You did include a lot of facts - so kudos for that, but it's very obvious that you're upset. You're not just presenting an issue that you think needs addressing, you've including a lot of fingerpointing at the individual you believe is responsible. You're DEMANDING an investigation the same as a disgruntled customer DEMANDS a refund.

The person your finger at is tell you - point blank - that he is willing to work with you and you're declining that offer because it's not the action you want taken. That's called being a director - you're directing those who are talking to you into doing something specific to your interests.