Re: Stopping 1 Gold Short (and the Platinum)
Garrant 3, the the 3 people blown up at once is pretty easy when you get to the jeep level. On the right hand side there is a barrell and 3 baddies that run out at once. Hit that barrell at the right time and you'll see all 3 of them airborne. It's pretty touchy so it'll take 5-10 minutes but it does work. Just reset to checkpoint at the first archway and you'll have it.
The mistake I made was that I was about a third of the way through Hard and I decided to do the steel fist expert and a few others so I played chapter select. Bad idea! I had to restart my Hard game all over again because it didn't have credit for those chapter ones I did. Might be Zrez's problem he posted.