Blurred recorded video into focused video

I got a few video recordings that I need to do some chroma key, but the problem is that for reason unknown my camera lost focus several times during the recording, and I was wondering if Blender has a node or sequence of nodes to remove the blurred parts / moments from the video / movie clip, so the chroma key effect can be properly applied

I am not sure if blender does or not but I do know that blurred footage with keying is a major pain in the butt even for Hollywood and even the compositing software I use has a hard time with blurry footage. Might have to key it multiple times but doing it in blender I am not sure how one would do that.