One clarification: Zebkit still uses Chromium's sandboxed renderer processes and shared memory internally. The embedding interface is a C API: your application links the library, keeps its own window and event loop, and can either embed a web view or receive off-screen frames to draw itself.
There's no Go binding yet, but the C API should be usable through cgo. If you give it a try, I'd love to hear where it fits your setup and where the integration gets awkward. Thanks for sharing your use case!