AX Email Approval - The Requested Workflow Action Failed.

We recently created a new Azure Service using SAS authentication. (Removed the old ACS Service Bus).
It worked initially, however, after a few days we were receiving the following error when trying to approve from the email link:

The Requested Workflow Action Failed.

In order to remedy this I found this blog post which helped:

http://msdynamicsaxtips.blogspot.com/2018/02/the-requested-workflow-action-failed.html

I took some extra steps which I will list out here:

1. Generate Full CIL on AOS which has the Mobile Connector software
2. Stop the RapidStart Services in the Mobile Connector software

3. Deploy the 'SysWorkflowApprovalServiceGroup'
AOT -> Service Groups -> SysWorkflowApprovalServiceGroup

4. Start RapidStart Services in the Mobile Connector software

After doing this, I was able to successfully Approve via email link.

I suspect that Step #3 is most likely what fixed this here, however, I think the other steps could be helpful.