What are the individual cell voltages? If they ended up severely imbalanced but none got too low or high you may still be able to keep the pack going a bit longer, but if any ended up lower than 3V or over 4.2V you should probably retire it.

As for the damaged balance leads, you can get a set of JST XH pins, connectors, and crimper, or you can cut the leads off your maybe dead imbalanced battery and solder them to your other one (just don't cut multiple wires at once and make sure you solder them in the correct order).