A 3rd party called Sherwood was brought on to wind down the company. This is common thing for a company to do when there are lots of assets to sell and loose ends to tie up. Everything from office furniture to domains to etc. They made all the decisions to sell what to who.
If anyone wants a startup idea, it's to make the inverse of Stripe Atlas. Closing down a company properly is a very long and complicated process.
This account doesn’t explain why your brother proceeded to misappropriated the startups database, and then terminated the rebranded startup once the wrongdoing was uncovered.
I'm skeptical a neutral 3rd-party would advocate selling credit card data to a person planning an illegal scheme. Especially when that person is your own brother.
If anyone wants a startup idea, it's to make the inverse of Stripe Atlas. Closing down a company properly is a very long and complicated process.