Let's say you are right and i do not have this information yet and i need to read more.
If someone is staying to steal, should have already the devices(1000+) ready and they have no ideea when someone will do the transaction or not. Even if they own or rent the devices and they have in standby, the money they spent for nothing are huge!!!
Let's say they crack in minutes before the transaction is made, there are multiple solutions without using
... [rest of BS]
So have fun!
I really hope you solve any puzzle up to #100. I can definitely re-assure you that the fail-safe methods you'll use will not be proven to be wrong in mere minutes (or rather sub-seconds for trivial problems like #71).
The guy who'd prove you wrong would probably either sleep or be at the beach, not staring on a screen waiting to spin up 1000 GPUs, you know?