Hi @anon23852708, thanks for reaching out! As it stands, the Asana for Tableau integration doesn’t support custom fields value history (e.g. how long did it spend in “awaiting review”). You can find more details in this guide article: Asana for Tableau • Asana Product Guide
I also recommend you to contact our support team if you would like to have more support depending on your use case: How to contact our Support Team ✉
I hope this helps!