You might be able to glue it with epoxy, but personally I wouldn’t trust it. It could allow stray voltage, leaching if metals, or just stop working that one weekend you decide to take a trip.
Just epoxy it. The electric motor in submersible pumps are usually sealed. If you opened up that pretty plastic you would see the motor was encased in some kind of resin.
I'm not saying that's always the case but it usually is.
I would leave it, or send it to the JV team to mix and move water for water changes. The epoxy could be more risk than using it as-is. Most of the plastic is for protection and looks. I have used pumps for a long time when the covers have broken or fallen off.