Yes, that controls the URL structure
mentioned in the first post:
Code:
###########/threads/217428/
Where and how are you adding links for that to happen? That doesn't seem right.
The only way that'll be true is if your vBulletin forum is still live. A 301 redirect isn't a "live page" where content is loaded (so it can't be a duplicate). It redirects you to a destination page and you'll never hit the content from the old URL.
If you feel like the issue is with the VB -> XF redirect, contact the person who set up the redirects for you to investigate if it's an issue or not. Check and see how many redirects it makes to reach the destination page.
But what's listed in the Google Search Console isn't telling you that's the reason why your pages aren't indexed. That's just a report that picks up ANY links you're 301 redirecting.