My brother in law died recently, we had very little interaction with him in the past 4 year. He himself was a guy from countryside Lithuania and not a very technology educated. He lived for past four years (and died) in Britain and had no spouse. His closest relatives are parents who live in the countryside Lithuania and do not speak any English nor has any knowledge how to deal with this sort of stuff. He didn't leave a will. My wife (his sister) does speak English, but not the type of person that deals with legal matters - which leaves this whole thing to me.
I have contacted bank that he was using (Card one banking) and have sent them copy of his passport, death certificate and other documents we could find at his place. However it now been 3 weeks and they are not responding to my emails. I am assuming because my surname is different to that of the deceased and they think this is a scam or simply do not care. How would I go around getting a proof that I am the person that is dealing with legal stuff after his death? I have paid for his burial could this serve as a proof of me dealing with this.