Getting a sharp blade in between the rubber button space and the fabric grill will help you prise it free. Obviously a sharp plastic spudger is better than a sharp kitchen knife to reduce damage, but the point shown in the photo is where the front grill separates from the speaker.
Anyone from iFixit that can help with this problem? Another thing that might just work is a dismantle and review of the part. Might turn out there's a pin slightly pushed out of place (possible easy fix) as opposed to the ribbon cable damaged (more hassle).