Check it out here: https://haileyedwards.net/dead-in-the-water/
YES. This book is set in the Black Dog world. YES. Thierry will make appearances. YES. It fits into the Black Dog timeline. (The events occur after Old Dog, New Tricks.) NO. You don’t have to read the Black Dog books first, but your reading experience will be enhanced if you’re already familiar with the world, previous characters and prior events.