Insurance Claim Repudiation.

I am in a process of challenging my insurer Dial Direct and recently Telesure. I have put in a claim but it was rejected because of BMW SA. My vehicle is ****** and two days after the keys shows that they have operated. The insurer does not want to tell who gave them information about the key data. I challenged them and we agreed to contact BMW SA. Instead the insurer consulted BMW SA employee who then wrote a mail to them telling that their vehicle are not manipulated and the key data are 100%. The insurer is now sticking to his email and don't want to consider and correspondance. I have just recently proved that you can operate the E90 3series without a valid and issued key. My problem is that who enforce the reporting structure because i received a formal letter from BMW SA with logos but the insurer does not seem to entertain the letter but rather the employee email. Where do you complain if all the company structures seem to have flaws. I am now loosing the Insurance Claim and that is because BMW SA intervened without facts on the table. I am now worried that the Ombudsman may end up taking their side beside all efford i take to prove my side. What must i do now.