New PWA site metadata error

I am using a workflow to create a project in project server 2013. This seems like a fairly common operation, but I need to set a few pieces of information when I create the project that are not available in the constructor.

Process Outline

for my own purposes I am using Chrome app DHC for creating these requests.

I use headers:

  Accept:       application/json;odata=verbose
  Content-Type: application/json;odata=verbose

1. get the Context (X-RequestDigest):

   dev1projects/PWA/_api/contextinfo [POST empty body]

2. Pick a Project:

   dev1projects/PWA/_api/ProjectServer/Projects?$Top=1
   [GET]

3. Check out the project:

   dev1projects/PWA/_api/ProjectServer/Projects('theguidi-just-pick-from-theprojectabove')/checkOut()
   //Add Header X-RequestDigest:0xTheStringFromTheContextQuery(d/GetContextWebInformation/FormDigestValue)
   [POST empty body]

4. Update the Draft item:

   dev1projects/PWA/_api/ProjectServer/Projects('projectid')/Draft/update()
   //Add Header X-RequestDigest:0xTheStringFromTheContextQuery(d/GetContextWebInformation/FormDigestValue)
   [POST]
   {"__metadata":{"type":"PS.DraftProject"},"Name":"Test 679"}

5. Check In the Draft:

   dev1projects/PWA/_api/ProjectServer/Projects('theguidi-just-pick-from-theprojectabove')/Draft/checkIn()
   //Add Header X-RequestDigest:0xTheStringFromTheContextQuery(d/GetContextWebInformation/FormDigestValue)
   [POST empty body]