Polyglot just exits without any error

[veqryn]

I've tried both polyglot version 1.6.0 and 2.0.0
I'm on Windows 10, and am using git-bash (shell).
I can't seem for the life of me to get polyglot to work at all, it just exits without any error.

The server I am running this against works just fine and is able to receive and respond to grpc calls from a golang process and also receive curl calls through a grpc-gateway.

Here are some examples:
In git-bash shell with 1.6.0:

MinGW 11:19:31 ~/workspace/go/src/xxx/xxx$ echo '{"rid":"abc123"}' | java -jar "C:\\Users\\xxx\\programs\\bin\\polyglot.jar" --add_protoc_includes=./include,./vendor/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis,./vendor/github.com/grpc-ecosystem/grpc-gateway --proto_discovery_root=./services/proto --command=call --endpoint=127.0.0.1:25051 --full_method=xxx.XXX/GetBlah
[main] INFO me.dinowernli.grpc.polyglot.Main - Polyglot version: 1.6.0
[main] INFO me.dinowernli.grpc.polyglot.Main - Loaded configuration:
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Creating channel to: 127.0.0.1:25051
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Using proto descriptors fetched by reflection
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Creating dynamic grpc client
MinGW 11:19:57 ~/workspace/go/src/xxx/xxx$

Here with 2.0.0:

MinGW 10:35:49 ~/workspace/go/src/xxx/xxx$ echo '{"rid":"abc123"}' | java -Dorg.slf4j.simpleLogger.defaultLogLevel=debug -jar "C:\\Users\\xxx\\programs\\bin\\polyglot.jar" --add_protoc_includes="./include,./vendor/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis,./vendor/github.com/grpc-ecosystem/grpc-gateway" --proto_discovery_root="./services/proto" --use_reflection=false call --endpoint="127.0.0.1:25051" --full_method="xxx.XXX/GetStuff"
[main] INFO me.dinowernli.grpc.polyglot.Main - Polyglot version: 2.0.0
[main] INFO me.dinowernli.grpc.polyglot.Main - Loaded configuration:
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Creating channel to: 127.0.0.1:25051
[main] DEBUG io.netty.util.internal.logging.InternalLoggerFactory - Using SLF4J as the default logging framework
[main] DEBUG io.netty.channel.MultithreadEventLoopGroup - -Dio.netty.eventLoopThreads: 16
[main] DEBUG io.netty.util.internal.PlatformDependent - Platform: Windows
[main] DEBUG io.netty.util.internal.PlatformDependent0 - -Dio.netty.noUnsafe: false
[main] DEBUG io.netty.util.internal.PlatformDependent0 - Java version: 8
[main] DEBUG io.netty.util.internal.PlatformDependent0 - sun.misc.Unsafe.theUnsafe: available
[main] DEBUG io.netty.util.internal.PlatformDependent0 - sun.misc.Unsafe.copyMemory: available
[main] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.Buffer.address: available
[main] DEBUG io.netty.util.internal.PlatformDependent0 - direct buffer constructor: available
[main] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.Bits.unaligned: available, true
[main] DEBUG io.netty.util.internal.PlatformDependent0 - jdk.internal.misc.Unsafe.allocateUninitializedArray(int): unavailable prior to Java9
[main] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.DirectByteBuffer.<init>(long, int): available
[main] DEBUG io.netty.util.internal.PlatformDependent - sun.misc.Unsafe: available
[main] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.tmpdir: C:\Users\xxx\AppData\Local\Temp (java.io.tmpdir)
[main] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.bitMode: 32 (sun.arch.data.model)
[main] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.noPreferDirect: false
[main] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.maxDirectMemory: 259522560 bytes
[main] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.uninitializedArrayAllocationThreshold: -1
[main] DEBUG io.netty.util.internal.CleanerJava6 - java.nio.ByteBuffer.cleaner(): available
[main] DEBUG io.netty.channel.nio.NioEventLoop - -Dio.netty.noKeySetOptimization: false
[main] DEBUG io.netty.channel.nio.NioEventLoop - -Dio.netty.selectorAutoRebuildThreshold: 512
[main] DEBUG io.netty.util.internal.PlatformDependent - org.jctools-core.MpscChunkedArrayQueue: available
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Using proto descriptors obtained from protoc
[main] INFO me.dinowernli.grpc.polyglot.command.ServiceCall - Creating dynamic grpc client
MinGW 10:35:54 ~/workspace/go/src/xxx/xxx$ echo $?
1
MinGW 10:35:58 ~/workspace/go/src/xxx/xxx$

The server itself doesn't show any logs or calls received/attempted when polyglot has reflection turned off.
When polyglot is using reflection, the server does show reflection grpc calls, but still doesn't show the actual grpc call I am trying to make.

What on earth am I doing wrong?