It seems the code [here](https://github.com/confluentinc/librdkafka/blob/ad90e9bbc5d16bb37a8f2c4554a36dbb4eefce5a/src/rdkafka.c#L5184) only uses `v0` of `ListGroups`. The [introduction.md](https://github.com/confluentinc/librdkafka/blob/master/INTRODUCTION.md#supported-protocol-versions) file however says v4 of ListGroups is supported. Please update code to use atleast `v4` of `ListGroups`.