Stuck Fresh Air Intake?

[Danielzore]

So this is my first time posting here, and I was hoping someone could help me since everyone here seems very knowledgeable. I am currently having troubles with a bent and stuck lever on the side of my wood burning stove
[Fireplace number: 143975 Model: KC-38-2 Grate model: SGR38 2 Blower assembly model: 11781 -There is no blower, but i did see what appears to be something a blower or fan could plug into on the bottom right.-]

The lever is bent in two places, and when I pull it to open it (as it says) it just bends. I can not see a way to get behind the metal insert without taking the tiles off the surround. The opening is very small, but I was able to see a tube leading from the wall to the metal insert. After looking on the roof it appears that there is a stack that would be the fresh air intake for the fireplace, as the site of the stack matches the location, and the two bathroom stacks are in different areas. Any advice on how to fix this would be great, as every time I have a fire we get some blow back, and I have tried numerous things to fix that problem.

Thanks!