I doubt if Adam would ask you to send it back as it's faulty and can't be re-used. He'd just post another one out. The main issue is that the casing is incomplete so isn't as good an electrical shield. But then you've got two single coils anyway, so they'll still be the noisiest pickups.
If you were planning on shielding the cavities, then you can always stick a piece of foil across the gap in the casing to restore its shielding integrity.
If you stick a multimeter across the output wires and get a DC resistance reading between say 6k and 10k ohms, then the coils should be fine. Only if you get a much lower reading (short circuit), or no reading at all (open circuit) would the pickup definitely be damaged. But the harness is pre-wired, so you'd need to unsolder the leads first. But you could plug the assembly into an amp and tap on the pickups as a quick check to see that they all do at least make a noise.