If that is the case I would move them indoors to an emergancy QT fasility which many members on this site make out of those large inflatable swimmimg pools say perhaps set up in your garage .
I have a Canadian friend who moves her own koi into her husbands Work hop to stop them succumming to temperatures as low as -26c and a wind chill of -54c wich was simply killing off all her koi each and every year.
Since our suggestion of moving them indoors she hasn't lost one koi .
You could also move your filtration with them as she has, if you feel the filter isnt mature enough buy some Microbe_lift PL filter pad innoculant follow Gel, follow the instructions and in next to no time you'll have a fully mature filter.
The glory of this is your safe in the knowledge that no preditor can get to your koi and you'll then have the time to find and either make good the repair to the pond or remove the liner and replace it
Dave
