Trying to show link “Use as featured image” from Attachment window

Hi, i found this great script from t31os who give me the chance to hide fields and buttons when we have to add images on a post in wordpress.

But one thing is missing the Use as featured image is not appearing. I have only the delete link. Is someone have an idea on how i can make appearing the link Use as featured image beside the delete link? It is the only thing missing from this great script but i’m not a php expert i try to figure it out but didn’t find the solution.

see code here https://pastebin.com/tvs3zTKT

Thank for any help.

Regards