The lever is actually called an "anti-billow device". It's purpose is to keep the slide fabric from catching the wind when driving and unrolling from the roller bar. If the fabric starts to unroll, the lever hits the stop on the side of the RV, preventing further unrolling.
From your picture, it doesn't look to me like the lever is bent. It just pulled out the screws (there are two screws). If the existing screw holes are no longer able to hold the screws securely, drill new screw holes through both the lever and the roller cap so that the lever is mounted in the same position. The lever needs to be positioned so that it misses the stop as the slide is extended, but hits the stop when the fabric starts to unroll when the slide is all the way in.
Here are a couple of pictures I took when I replaced the fabric on our slide.
Removing the anti-billow device.

Anti-billow device adjusted to miss the stop as the slide goes out.
