I’ve used several of these exchangers listed on BestChange, and they’re practically impossible to use for money laundering. For every suspicious transaction, they ask for documentation.
So unless the BKA is lying in their press release, what you say is bs. The services were seized because they failed to fully comply with AML and KYC laws, so if they didn't, how come they are so strict in confiscating customers funds and rarely ever returning it back to them. It can only mean one thing, and that is that this services used the excuse of 'suspicious tx's' to steal funds from their customers and keep the money for their own benefits.