Hello:
In the future please don't attach your INI file - it contained your client ID and secret (I've removed the file from your post). Please delete that client ID and secret in the Google Developer Console for security reasons and generate a new one.
As for your issue, PHP's SOAP gzip compression levels are positive (1 through 9). A value of -1 isn't valid and is causing this issue.
Thanks,
Vincent Tsao, DFP API Team