The Storage::url() method simply generates a URL, it doesn't actually check if a file exists at that path. Storage::get() attempts to find the file at the path you give relative to the base path of the disk.
By default, the "local" disk is used. It stores its files in your-project/storage/app. Using Storage::get('app/public/img/reportImages/...') would cause it to look in your-project/storage/app/app/public/img/reportImages/... which is probably not the right path.
As Snapey said, you'd need to get the full path like: Storage::disk('public')->path('img/reportImages/e96b4467-055d-4e5a-8c4e-bf2af6261177.png') (notice that the disk is being specified by first using the disk() method and that the path is relative to that of the "public" disk's base path - your-project/storage/app/public)
@Snapey I don't believe I did anything wrong here. I simply expanded and added clarification to what you said (some people need things explained explicitly, I know that I do sometimes). The OP posted practically the same question yesterday, to which one of my replies also advised them to use Storage::path() as well.
I misunderstood the method, my mistake ... but it did end up being a problem with my route. I needed img/reportImages instead of app/public/img/reportImages. Thanks