Need help with attachments

I am trying to create a simulation script that calls a rest service and upload a pdf document.

I created SOAP UI to test this scenario and it works as expected.

When I run the Gatling simulation script to do the same , I am getting - ><ns1:faultstring xmlns:ns1=“”>java.lang.StringIndexOutOfBoundsException: String index out of range: -1</ns1:faultstring></ns1:XMLFault>

It seems the Apache Cxf parser is not able to process what the Gatling script posted.

Below are the Gatling simulation Script, SOAP UI raw request and Gatling raquest data.
One thing I noticed is that SOAP UI identifies the Content-Type: multipart/form-data, while Gatling identified the Content-Type: multipart/form-data and Content-Disposition: form-data… should the Content-Disposition also be multipart/form-data .

Also, the binary content of the pdf file in Gatling looks bit different than compared to SOAP UI binary content.

Any help will be appreciated…

My Gatling Script…portion of it