Email Massage Input to Text/Excel Input

Scenario:
Download attachment from mail and read it in the same workflow. Mail input creates a new unique folder and attached files are kept inside that folder so I want to read that file inside that mail folder.

In the email message input step, the attachments are downloaded in a Mail subfolder and that folder location is in the AttachmentFolder field. When I pass the field to the next text/excel input plugin it gives an error and sometimes it fetches but that input plugin puts values to each and every coming field, not into the specified fields.
How to use input plug in which is not a start node and has coming fields.
Please help with detailed evaluation else don’t confuse me more.