[Taek]

Seems unlikely that the FBI sitting on a way to break ECDSA would use it to recover $2 million. Much more likely that there was a tumbler or exchange that they were able to link to the attacker and use to seize funds. Maybe they even have backdoors in some popular crypto wallets.

[mmaunder]

Might cost more than $2MM in compute, but could be worth it to demonstrate capability.