We are oral cancer patients and care givers without medical degrees so its very unlikely anyone here would be able to give you an accurate diagnosis from seeing a couple photos. What did your doc say to cure this? The white coating almost looks like thrush to me. But Im not qualified to really try to guess what it is, especially over the internet. Regardless of what caused this, how is this cured? What have your doctors told you to do about it?
One piece of advice.... QUIT ALL TOBACCO IMMEDIATELY (and permanently)!!!! I cant stress this enough. There are many known cancer causing additives in all forms of tobacco. Those additives probably play a big role in your illness. By eliminating the tobacco and giving your mouth a chance to heal it will definitely help. I know for sure it wont make this worse!
Best wishes, I hope you get well soon.