A few points of note (without me injecting my conclusions)
Crypto ransoms take a high degree of skill to pull off. POI would need to understand how to cold store BTC. Not on a hot wallet like Ledger. True cold storage takes sophistication and years of planning (storing keys and sleepy wallets with NO prior transactions). After the ransom is paid, POI would then need to use a crypto mixer like Monero or similar to breakdown the BTC, send it to hundreds of wallets, wash the hashes in thousands of transactions and then recollect the BTC once its been washed. After all that, they’d need a laundering scheme to convert the cleaned crypto into fiat. This person(s) would NOT send notes to the media. They understand anonymity and would avoid hot contact (I.e internet contact)
If you’re confused, you’re not the culprit. That gives a sense for the kind of person or persons skilled enough to pull off a crypto ransom. And that says nothing of the skill to kidnap someone. Those are two very different skill sets that rarely occur in one person.