I believe there's some confusion in your code around the "Edit Others Posts" and the "Edit Private Posts" capabilities. Even with "Edit Others Posts" checked, my editors were unable to see the full post list — going to "All Posts" showed them only the articles they had created, and they couldn't see "Edit this entry" on any post but ones they'd created.
After some troubleshooting, I narrowed it down to the "Edit Private Posts" checkbox. If this is checked, editors seem to be able to see and edit all posts, both public and private. So something's wonky there.