The problem is that Stripe has identified you as possibly being a fraudster. Any information that they give you about what they suspect and why is information that a real fraudster could use next time to try and evade the detection algorithms.
It is like this with virtually any security system. Adding feedback you can use for debugging also makes the system much easier to compromise.
How many fraudsters are maintaining a business relationship for 6 years? 6 years! And the OP doesn't even get a courtesy phone call before termination. That's messed up.
One of the attacks that fraudsters have developed is to buy businesses to use their accounts for fraud. That going out with a fraudulent bang is better than trying to run a marginal business.
It is like this with virtually any security system. Adding feedback you can use for debugging also makes the system much easier to compromise.