The reward for finding one of the FBI's Ten Most Wanted Fugitives is a "minimum of $250,000."

https://en.wikipedia.org/wiki/FBI_Ten_Most_Wanted_Fugitives

Are authorities serious about getting these people or not?

It should be at least $1 million, especially with inflation and their notoriety.

There's likely a price where insiders would turn against her to make some bank.

You'd think there would be a group of cashed-up BTC/crypto enthusiasts willing to chip in to fund this reward.

It would be an OG move by Satoshi Nakamoto or another anonymous BTC/crypto holder to offer a bounty of 40 BTC (roughly $1M) on top of the $250K by the FBI (US Gov).