On SERVER-88548, we changed the behavior of checkShardingIndex command to throw an InvalidOptions error instead of returning an UnknownError, so that there was no need to translate it at the shardCollection operation level.

However, in a multiversion scenario, we may still receive an UnknownError from a checkShardingIndex command running on an old binary node that has to be translated to an InvalidOptions error.

So, we still need to translate an UnknownError to a InvalidOptions error until v8.0 becomes the last LTS (note that we will backport SERVER-88548 to v8.0 before it gets released).