Forge API: How do I get the geometry of a 2D floor plan using Forge API

I have looked at the model derivative API and it looks like the translation to obj format is only supported for 3D views

I tried the following call but, I get a 406 in Postman. Using the SDK I just get an error saying "Error calling translate" when I try to translate a 2D view to OBJ format.

curl --location --request POST 'https://developer.api.autodesk.com/modelderivative/v2/designdata/job' \
--header 'Authorization: Bearer xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' \
--header 'Content-Type: application/json' \
--header 'Cookie: PF=nwPYHj1XgpJV2XlRsRiOCi' \
--data-raw '{
    "input": {
        "urn": "dXJuOmFkc2sub2JqZWN0czpvcy5vYmplY3Q6dTE3cGo5NDF2YWp2b2J4eGg2a3pqYW12ZGczdmphYXYtYnVja2V0ZnJvbWFkYXB0ZXJzMS9naC1zbW0ucnZ0"
    },
    "output": {
        "destination": {
            "region": "us"
        },
        "formats": [
        {
            "type": "obj",
            "advanced": {
           "modelGuid":"9ed324d6-2da9-9d68-5a02-b420bf73b327",
           "objectIds":[16749]
        }
        }]
    }
}'

How do I get X/Y/Z coordinates of a 2D floor plan using the Model derivative API?