All I can advise you with is front up with a lawyer. And the penalty will not be so severe. DO NOT do it on your own. Otherwise you will have lots of problems.
It’s obvious it was a scam. Don’t deny it. They were caught legitimately. Thai Immigration now have all the information they want to contact those who use there illegal services. It’s that simple. Better those caught front up at Thai Immigration and explain why they use there services. Thais are not stupid as we all think they are.
Better you get lawyer and go Immigration with him and explain why you do.
Those who have dealt with Thai Visa Centre better get a Immigration lawyer and go to Thai Immigration - rather than wait for them come to your residence and arrest you.