Dart Client : Dart interop using GRPC broken

I am using sandcastle, and having issues with making a Sandcastle Dart client

The intent is to have the Dart Client use the SandCastle GRPC's

Here is the issue i raised with the team. Complete test case to reproduce is there.
grpc/grpc-dart#116

EDIT: Btw golang and dart grpc interop used to work. But it broke recently with the dart update to dart SDK 2.0. SO its just a matter of time until it works again.