what exploded hardware?

Basically because the record keeping laws in place to guard against financial fraud in major institutions also mandate a level of data redundancy and immutability that incidentally guards against such tampering to a level that approaches the US military. Every file creation, update, delete is revision controlled.

Imagine a fictional financial institution, let's call them Jigglypuff's Professional Money Cabal. First, they don't even have root-user access on their own storage. They can't override the legally mandated retention policy -- even in the off-site backup systems -- without a kernel patch that can't be installed unless it's signed with their storage manufacturer's private key. And at the first sign of compromise, the Cabal runbook is to just immediately flatten the whole thing, reinstall a clean system, and restore from the nearest geo.

Even if you go full Fight Club and physically destroy the buildings, in multiple cities, they've got another fully redundant and air gapped disaster recovery storage system literally in a bunker underneath a Colorado mountain.

all knowledge disavowed, and all hardware to do said crimes exploded