The article you link does not state at all what you claim.
It says that no payment processor is willing to provide them service. Not that they are not allowed to use that payment method. So yes, it would be legal. And although the result of nobody processing cards for them is that they would no longer be able to accept cards, it would have no relation with card fraud.
Although this 2018 article states that no processor would take them as customers
- it may be that some payment processor has been taking them again by now
As with any card charge, you may dispute it if you feel it wasn’t proper (such as being offered something at a give price but being charged a doubled amount). Although, if you didn’t agree on the service costs beforehand, I suspect that would be “proper amount” (they could choose to be expensive). Also, you might prefer not to bring much light to thisi charge (and thus the type of service you were paying for).