Media Image Number not working

Hi,

I have the following feed:

http://inline-reddit.com/feed/?subreddit=edc

which has the reddit thumbnail image and the imgur image.

I want to select the larger full size imgur image and set that as the featured image using autopost.

I’ve tried using multipe media image numbers but can’t seem to get it to not use the thumbnail image. Any thoughts?

https://wordpress.org/plugins/wp-rss-multi-importer/