ifIf the doctorDoctor spoke his name then they would know that it would be safe to come through, but all this time they must have grown more tardisesTARDISes or could have shared them and as soon as they come through they all escape to different time periods and places, galifreyGallifrey would be completely abandoned so there wouldn't be anyone to be killed and the daleksDaleks would all leave as soon as they realise there's no point attacking the place. Since no other race has mastered time travel like they have, they can all agree to rondezvousrendezvous at a time when the daleksDaleks are extinct (like around the year 100 trillion)and and plan to rebuild their civilisation (or make the final sanction at the end of the universe, there's nothing alive anyway). The citizens of Christmas could also be saved as the doctorDoctor can fit them all into his TardisTARDIS.