That's just a story. If you want to use this story, then you have to provide evidence that it is factual.
Irrelevant. The claim is the christian god does not heal amputees. It was demonstrated otherwise with the verse. If someone said why doesn't spiderman climb walls I could simply open a marvel comic and prove that he does. Story or not is irrelevant..
You also have to prove that God doesn't heal amputees. Oddly you don't take issue with supporting a non factual statement like this.. You also can't claim "well god doesn't exist". That itself would base the question on a false premise, and then doesn't qualify for a proper response.
It's also very telling that whenever the subject comes up, this is the one and only example that anyone can point to. 2,000 years, and god only has one example on record? Not. Very. Impressive.
So it would have been more impressive to record more bodily limbs being healed? Then you would have taken issue with how many limbs hes restoring and why he isn't doing it more frequently. The fact that their is only one healing of a limb in the bible would only attest to its rarity in occurrence.
People have their limbs saved all the time from dismemberment. Who's to say that this isn't Gods method by preventing amputation. It would make more sense than healing someone who is already amputated. That would be a inconsistency in Gods character. So maybe that victim prayed to have his arm or leg saved? Maybe that doctor prayed for the ability to heal, or save that victims limb. If god did not save your leg in the first place from being amputated for whatever reason, what reason is their to assume he will decide to restore it after the fact.