Hi Kris, 

Unfortunately there is no researched recipe for home canning of diced tomatoes. Your research into the matter is correct. I know that this is on the "wish list" of many home canners, but no research has been conducted to date. 

The closest analogues in the research-based literature would be the recipes for crushed tomatoes or tomato halves, both of which are included in the Extension publication I'm attaching here. Because each style of preparing tomatoes changes the density of the product inside the jar, different processing times and acidification procedures have to be tested to ensure a safe product. 

Thanks for reaching out, and thanks for using tested recipes to can your tomatoes safely.

Best, 

Jared