Company named Avante called my son's cell phone

My son is 13 and was home sick today when he received a call on his cell phone (number we have owned for over 2 years). They asked for someone that we don't know (for protection i will call him John Doe). My son told the person that they reached the wrong number. The person on the phone acted as if he was lying and told him to put his dad or mom on the phone. He told the person that his mother was in the shower and that there was no one there by the name she mentioned. She told him that he was lying and that she spoke to John Doe at this number on Dec. 5th. He said that was not possible. Again the person insisted on speaking to a parent. My son again declined and said that his mom was home but not able to come to the phone. The lady on the phone told my son that she was going to send someone to the house to check. At this point my son is very scared and hangs up the phone and calls me. I get the number and call get the lady on the phone that spoke to my son. She kept insinuating that I was John Doe and that i was lying to her. I told her that i did not know this John Doe to never call the number again and that i wanted to speak to her manager about the comment about sending someone to the house. The manager told me that they would remove the number from the account and he was sorry.

Now I am not sure if this is some tactic used to get my real name for some debt collector, but dont I have rights to prosecute this company for scaring my child? Where do they have the right to call and do this? Where can i find fair collection rules or regulations for these type of agencies?

Thanks.....