Not sure why/if this could relevant, but the tags for app deep-linking were added after the site was approved for cards a long time.
Here is an example of a tweet that should show the “open in app” link but always shows “view on web” instead:
the twitter meta tags are as follows:
I’m unable to see the “open in app” link when the app is installed, or the “install app” when it is not.
Thanks.