A repair is always possible, but depending on how damaged it is in the segment it might need two joints and a new small section inserted.
But I would start by cutting mid-damage and seeing if it looks clean enough that it can simply be joined in a suitable torpedo style of resin joint. Something like this:
As the cable has not been installed yet you can easily do an IR test (having checked the far end is clear of any shorts, etc) to get an idea if it is OK even before you start cutting (which you should not do until you are ready with a joint to finish it).
Edit: I would try and simply part the cores, etc, without cutting through, it is best if you don't have actual joints and simply use the resin unit to allow it to be inspected and covered over if no real damage is seen.
But I would start by cutting mid-damage and seeing if it looks clean enough that it can simply be joined in a suitable torpedo style of resin joint. Something like this:
S6 1.5-10mm Straight Resin Joint Kit for Cables up to 10mm 2 Core
Proven underground cable jointing system
www.cef.co.uk
As the cable has not been installed yet you can easily do an IR test (having checked the far end is clear of any shorts, etc) to get an idea if it is OK even before you start cutting (which you should not do until you are ready with a joint to finish it).
Edit: I would try and simply part the cores, etc, without cutting through, it is best if you don't have actual joints and simply use the resin unit to allow it to be inspected and covered over if no real damage is seen.