A delivery receipt comes from the receiving server, and many servers never send one. A read receipt comes from the recipient’s program and needs their agreement. A short line such as “Please confirm that you received this” often works better than either.
HawkOpen does not send receipt requests. For each tracked email it shows whether your sending server accepted it, whether it bounced, and when the tracking image was loaded or a link clicked. Those are signals, not a confirmation from the recipient.