Hum, something doesn't sit right with what you just described. If the camera in focus green dot comes on solid then the camera is saying the image is in focus. Did you just drop the lens or was the camera attached to the lens and the whole assembly hit the ground. Lets back up some more what is it you are trying to focus on, meaning the camera will be confused solid colour, no contrast, glass, water, chrome. Or trying to focus on something to close for the lens optics yes I know you said Macro but even macro but even this lens has a minimum focus distance. Check your specification sheet that came with the lens. Okay another thing and this is a biggy if you are trying to focus on something at F2.8 close in the camera may catch focus but the DOF is so shallow you can't actually see the focus point and everything appears out of focus. Okay another thing, lets say you have this lens mounted on a tripod at a setting of F11 and a shutter speed down into the 1/50 or even a bit slower, your think you are okay because it's on a tripod right, nope just by you tripping the shutter you have moved the camera and the pictures will be blurry under close examination. In this case you need to do one of two things or both. You can use a 2 second shutter delay and or mirror lock up. I use both when available. I've even gone to using an electronic release in some cases. So if the camera in focus light in the lower right corner of the viewfinder comes on solid then the camera has focus. If the lens was off a bit the in focus light wouldn't come on or if it did it would flicker and if it's not got focus the shutter couldn't be released. So sorry I think it's one of the other problems I mentioned. Hope I helped and not confused you to here is a sample picture a center crop of a much larger picture the scene was 3/4 mile away.
It's pretty crisp but the sizing took a bit the original you can count the brick on the building.