How to send a webform email to all users of a specific role?
From the exported rule in your question, it seems you already have the Webform Rules module enabled (a prereq for what follows ...).

You may want to give it a try to process the results of a VBO enabled view via Rules, whereas your rule performs 2 Rules Actions:


Load the VBO list that you want to be processed.
Add a loop to perform a Rules Action, for each row contained in your Views results.


Some more details about the VBO-view you'd have to create for this:


Create a list users, using the Views module.
It should include an appropriate filter for the role to be processed.
It should have exactly 1 result (row) for each user to be eMailed.
One of the columns should be the eMail Id (I don't see other columns needed for this to work).


For more details, have a look at the tutorial "How to process the results of a VBO enabled view via Rules?".