While not nessacarilly a cheat, it is cheap. Select the 2 infantry squads and engineer squad you start this map with, and right click the command point your supposed to capture at the top of the hill. While they are making thier way up, quickly fill your barracks queue with infantry and the BAR upgrade, then follow the group you sent up progress. Towards the top they will come across the artillary spotting tower which you need to take out for the medal. fill it up with grenades to take it out, and quickly garrioson it when its clear. now a Panzer and a fire truck might block the road up to the top, just quickly pop in and out of the tower and toss sticky bombs on the panzer. You might lose this first squad but its ok. Back at base just keep producing infantry until your population cap is reached, group all squads in 1 and right click the command point at the top of the hill and start your violent exodious. ignore most the treats on the way off, but dont hesitate to sticky bomb any of the fire trucks that might stop you, as soon as thier taken out right click on the command point again. The sheer mass numbers is too much for the enemy to wipe out completly so your squads will make it through though probaly 1 or 2 to a squad once thier at the command point its hard for the enemy to dislodge them, and viola, easy way to beat a hard level.
Although this isn't a cheat is is easy to do. Earn at least one command point and get the Air Recon ability, then recon at the enemy HQ. The AA guns there should shoot your plane down but the plane will go into the enemy HQ and do lots of damage to it. Do this three times and the HQ will fall and the Medal for doing it is yours!