Fact: Would you believe me if I told you I got the private key to the 31000btc
No, because you won't dare to post it here in the first place.
If that happens, it's possible more lost Bitcoin to crack for you.
Conclusion: As a newcomer before the year 2040, Bitcoin would be cracked by ethical hackers period
IMO, it's technically possible for lost Bitcoin to be cracked by ethical hackers, but it would be extremely difficult and unlikely to succeed.
It might the method you've used would require a significant amount of computing power and spending a lot of time which is the chances is very low.