This IS the screw head side thinking I am going to have a good time here as you can see no slot left
Is your rubber strap pliable enough to compress it and expose enough of the screw shaft between the lugs to get tiny needle-nose pliers on it? That would be much easier than messing w/ the screw ends. A (very) little hair dryer heat can help soften the rubber and loosen up those stuck threads. Tape off the inside of the lug to prevent scratches.