IMHO, the installation instructions provided by the mfg. are to be followed, as they should be compliant to the NEC, along with the UL, or other listing agency requirements.
IF the pump came from the mfg. with a 'cord connector' and the instructions specify 'cord', then that would be a compliant install, again IF the pump is being used & installed as per mfg.
Usually, equipment intended to be field 'hard wired' does not come with any connector at the wiring compartment, just provisions (knockouts/hubs) for field connection.
