Need Help Unlocking Achievements in Operation Flashpoint Red River

Okay, so I was using the GFWL Achievement Manager (this one: http://www.dev-c.com/misc/gfwlam/), and it was working perfectly for the base game. But it doesn’t seem to unlock any of the 5 remaining DLC ones. I tried also unlocking it on my xbox using Horizon and Velocity, but of course they have an issue with sticking and next time I log in they’re not there.

Now, when I go to click “view games” on the GFWL overlay it says I have 50/50 achievements, but when I go to look at the achievement listing itself it says I have 50/55 (on both my 360 and Xbone as well). I do not own the DLC for this game, but that wasn’t a problem when I unlocked the DLC achievements for Fallout 3 and Bulletstorm before without owning their DLC.

Can anyone please help me solve this issue? I would really like to be able to get those last 5 achievements for this game.

Why didn’t you just use Horizon to begin with?
Did you try recovering your profile?

I tried recovering my profile a few times. Also I originally used Horzion on my xbox, but since these achievements are from a Windows Live game they wouldn’t stick and would disappear. The achievement manager I used was fine until now, and for some reason won’t unlock the last DLC ones for that game.