Add Attachment to Task via Workato (Wrike Integrate)

I'm trying to move an attachment from a task to the parent task via Workato. 

I have a script that triggers a status change on the subtask, lists the attachments, filters for a specific one, and then gets the file's URL. I am using the File Handler module in Workato to download the file from that URL.

When I am trying to add it to the parent task, I'm running into trouble. Below is the path I am using on the Custom Action module.  

With the following Headers on the request:

I'm using the file URL instead of the File download per this article. But I also tried the output of the File module download mentioned above. 

The result is it adds an attachment to the parent task, with the correct file name, but it's like a "shell" and the actual file does not exist. 

When you try to open it you get the following:

The only thing that I can discriminate that is different from what I'm doing vs what is in the article I linked is that it is through Postman vs me using Workato. 

I'm not entirely sure how to accomplish this in Workato using the Custom Action module. Any help or direction from the community would be greatly appreciated.