Workflow failing in the second iteration

ISSUE:

The workflow we require is a multi-approval workflow which means once the author create the content it gets reviewed and approved by 2 roles (First by a Brand Manager and then finally by a Brand Director). The workflow works as expected if both Brand Manager and the Brand Director approves the content in the first go. However in a specific case where the Brand director is rejecting the content the 2nd iteration breaks. Below is the flow which is breaking (Steps to reproduce):

1. Editor create the content and send it to Brand Manager for approval. (Use any geometrixx page. Put it in the workflow and from the inbox assign it to manager.)
2. Brand Manager approves it and send it to Brand Director for the final review.
3. Brand Director rejects the content. (For the rejection process we are using a custom process. The source code for the same is in the attached bundle. We tried using the go to step available with 5.6.1 but it doesn't seems to work.)
4. The content is now back with the editor with the rejection comment.
5. The editor changes the content and send it back to the Brand Manager.
6. The Brand Manager approves the content and send it to the Brand Director for the final approval.
7. At this step the Brand director is unable to do anything. He is not able to approve/reject the content.

 Package details:

I do have a package which one can use as is to reproduce the issue on a vanilla instance of AEM 5.6.1. However just learned that i cant attach a zip file in this forum. Anyone willing to help me please reply back and i can share the package by any possible way.

Screenshot:

Here is the screenshot of our workflow model.

 [img]acme workflow.PNG[/img]

Appreciate any help in investigating or suggesting if anyone has achieved a similar flow using a different approach.

thanks,
Himanshu