If you can't spot the odd one out just move your head closer to your desk and look up at your screen. You'll probably immediately notice the glowing piece of paper
Just now seeing this, but lol. For anyone else that does this, I've redeemed a lot of vouchers in my time. My eyes automatically go to the voucher. As for those that rename multiple items and put them in there (cough someone yesterday cough), I actually picked the iron voucher out first time, then had to go through and see what else was in there for curiosity sake. You'll have to try harder than that to thwart me =P