We've been having issues for months now autoposting with many of our clients Facebook pages. Basically, we've figured out that it seems to be a time related issue. Facebook's bots don't have enough time to scrape for data before the posts are pushed out, which is why they're going out without some or most of their open graph tag information.
It'd be really great to have the ability to determine what time you'd like to have a post autopost to social media in addition to when it posts on the website. Having this kind of control over posts gets rid of issues like this, and makes the lives of our clients way easier. Not to mention our own lives.