Coinpayments have an hidden service (onion) url available.
He should expect to have his account closed and his funds taken away If he the website he's building is meant for something illegal.
In fact, he could expect the account to be blocked in any event using a 3rd party service, and they will provide an excuse if he's "lucky", any arbitrary reason is enough according to most terms of service. I'm sure many merchants, legitimate or not, will have experienced something of the sort.
Just grit your teeth, get things done yourself. The learning curve should be overcome fairly quickly with open source solutions with good community support like BTCPay server... Any business wants to do it seriously will have to consider this route sooner or later.
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