When squirrels ate my charcoal canister, auto insurance paid the $1246 the Toyota dealer charged to replace it, no questions asked and no increase in rates. I wouldn't attempt a wiring harness repair on today's vehicles - they are so sensitive to voltage and resistance (just look at the range in which the delta between the forward and rear oxygen sensors operates in <1V and then in almost unlimited increments of that 1V). I don't know about warranty, but know that you open up the possibility of corrosion over time at the repair points, almost guaranteed a change in the resistance value through each wire repaired and potentially a small change in the voltage and/or amps delivered. If your insurance will pay to do it the right way, then that's the route to follow.