If the matter is not bonus related it must be due to identity issues or a betting syndicate. bet365 is an operator with an outstanding reputation who would not lock accounts without valid reason. If the well known mediators are even refusing to look in the matter, the case must be an obvious scam. If you are looking for a hacker to access to these accounts for you, good luck. If you feel you did not violate their terms, there are various options to pursue this.
I would have been curious to understand the reason behind this ban and see what can be done, but obviously you are not interested. Your loss.