This is just a hypothetical question. Do you think that the 'shaikh' actually did something against the law and can be reported? Brother Dawud involves with some charity program there. Not sure though if he can help or not. Perhaps try to get mods to allow for personal contact details between you and brother Dawud? Also may be some other brothers/sisters from England can help with the situation here? Have you actually tried contacting a few da'wa/Islamic charity organizations in the UK? Perhaps they can guide you to the right channel to solve the issue (both legally and from Islam point of view).