How to use the Convert Anchor Point tool

Hi,

I have a traced an illustration which I want to alter the perspective of.

As you can see, I have first revised it using the Envelope Mesh tool. It is divided it into two vertical columns and one row. I want to 'break' the two columns', center anchor points so that  each would follow the flat plain the dark teal line would dictate (at top of image). Essentially, if achieved correctly, the two semi-straight lines, above and below the B&O text would be perfectly straight, following the dark teal line at the top. 

I tried using the Convert to Anchor Point tool to break the needed anchor points, but it won't respond, unlike when I am not using the Envelope Mesh tool.

Any help would be much appreciated.

Sand Patch