Eventhough this can happen, if something like this happens you can take them to court with an allegation like that.
A provider should be Neutral I have worked with Sysmaster and never had a single lead of VOIP business eventhough managed traffic to Cuba, Somalia, etc on my boxes, you had a bad experience probably.
Are you talking about somebody specifically at Sysmaster?
Solution: Do not use real customer information in your customer information area 🙂