Help with Named Ranges used in Validation Lists

Hello, I am attempting to use the solution you've provided here in a workbook I've been tasked to build. The workbook (attached) has two sheets: "Tasks" and "Required_Activities".

•"Required_Activities" breaks down the process for getting a job done.
•"Element"
•"Subelements"
•"Activities"
•"TaskList"
•"Role" assigned to perform the task

In an effort to gather metrics, the "Tasks" sheet has a column for the user to select a "Role" (C2). I have the "Role" validation drop-down working, except the blanks are displayed. Ideally, based on the role selected, a validation list displays the "TaskList" (D2) for the Role (my second attempt at validation drop-down list not working). The Activity (E2) would be automatically populated based on the "Task". The Subelement (F2) would be automatically populated based on the Activity. The Element (G2) would be automatically populated based on the Subelement.

Any help and/or guidance would be greatly appreciated!