I will say that I am a Firefighter and we are trained in high angle rescue (buildings, scaffold, etc). We are told that any rescue rope that has had a dynamic load (stretched) is no longer able to be used for safety reasons.
Be glad it worked, and go spend $50 and get a new one. Glad all was alright and you were not hurt.
And take the other one and throw it away immediately so you are not tempted to use it again for any reason.