purge vcm record using vco rest api?

Has anyone been able to purge a vcm record using vco's rest api function? I know the purge function is not included in the vcm package, however, we received what is supposed to be the raw xml code to do such a thing. I'm having trouble getting it to work. I created a workflow with inputs ID and Content and it spits out a status code 400 error. Has onyone attempted to get this to work?

Thanks!