can you explain why you believe the inner cable would be destroyed . If the outer cable sleeve is lined up and has no movement and if the outer cable is filed to taper so there is no burs from metal reinforced spiral. also it is a temporary fix till the weather warms up.
Sure can.
The outer housing is usually a helix wrapped wire. Usually that is square wire butted side to side and sized to fit the diameter of the inner cable fairly closely.
Once it is bent or broken, the sharp edge of the broken wire will rub the inner cable, cutting it completely or damaging it. Then the stresses and alternating stresses will fatigue it every rotation until it fails.
I don’t think that a human being has the skills and dexterity to align the ends of the sheath to get it very close to aligned, and to eliminate the sharp edges of the broken sheath.
Now if you have the skills of a watchmaker or jeweler then you might be able to pull it off with enough patience.
And the cost of a new cable is not too great to justify the time and risk.