I would either fix the block or applique something that will represent his life over it. Maybe the mascot for the college he's going to, or a favorite hobby. Or, can you cut all that interfacing away until there is just a fringe left at the seam line? Then you could just applique a small border around the block, covering that icky seam and call it done. In quilting, mistakes make us think outside the box. This is your opportunity.