Restricted multi origins release source maps issue

Hello,
I have an issue with release JS source maps. I’m working in restricted area with multi origins and assets are not public accessible, that’s why I’m uploading artifacts to Sentry. As documentation says I leave out --url-prefix parameter and my artifacts are prefixed with ~ (tilde) . When error is thrown however I can’t see source tree and there are errors like Cannot fetch resource due to restricted IP address ....min.js. My source files and source maps are uploaded to release artifacts and release is passed to Raven config. In this situation why Sentry tries to fetch my source files since they are already uploaded?

Thanks in advance
Mladen