Eh, I feel like this is blown out of proportion.
Firstly, if the defunct company was a user of various tools, unless they keep paying the bill (unlikely), then their services will be terminated and ultimately, deleted, along with their data.
I feel, whoever set up these services for these defunct companies in the first place, wasn't doing things correctly. Things like secrets, should never be able to be exploited after a domain or service stops existing (or even whilst it still exists).