edbae5d#diff-64b4460fd28efb376a5cd7aafc925085R551 fixed interceptor batch method FailHijackedRecvMessage for CallOpRecvMessage, but not for CallOpGenericRecvMessage.

CallOpGenericRecvMessage:: FinishOp() still bails out early if the call is hijacked_, here:

...which means this condition will never be true:

cc @yashykt