A workshop draft is a rough draft with corrections on it.  It usually makes suggestions to the writer on how to make the paper better.

Its purpose is to improve the draft into a final paper.

The difference between a workshop draft and a final paper is that a workshop draft is not finished but has many corrections.  A final paper uses the corrections in order to improve.

I would tell the writer of Essay R to check over his grammar.  I would also tell him to add a thesis and add more resources.