In LookupIn last command is not always parsed correctly

Given code the following code where the document "Lookupin_test" does not contain a field "hack-to-fix-last-always-1", the status of -1 is returned instead of the proper missing field status:

var key = "LookupIn_test";

var lookupInBuilder = bucket.LookupIn<dynamic>(key);

lookupInBuilder.Get("click");

lookupInBuilder.Get("with JSON");

lookupInBuilder.Exists("hack-to-fix-last-always-1");//will result in MISSING_PATH

var result = lookupInBuilder.Execute(); 

The Message field is correct, but the response status for the field is not because an internal parsing error keeps the response status from being set.