Knowing the behavior patterns of the guards here will help you take them down quickly.
When you've reached Tarfful, you'll need to quickly slice or breach the door next to him to reach the landing pad. Breaching it is the preferred method; although your teammate will chuck in an EC grenade at Grievous' bodyguard and miss, you can improve on his aim by throwing an EC grenade of your own at the droid's feet; since it jumps to avoid the first one, it'll land right on top of your own grenade, stunning it long enough to let your guys get inside the room.
Now, there are two of these bodyguards, but luckily only one will appear at a time. They're maniacally tough to kill with your normal weapons, so you'll want to set up your troopers in the sniping and anti-armor spots in the landing pad. Hopefully they can get there while the bodyguard is flipping around in the air, as having people in those two positions is crucial to actually winning the fight. The trick here is that sometimes Tarfful's scripting will break, and he won't follow you into the arena for the fight, so you'll have to take on both bodyguards with just your troopers. It's tough, but not overwhelmingly so.
After both of your troopers are in position, you can have the third one attempt to lure the bodyguard in for close combat. Your first priority, though, should be to stay the hell away from these guys; your troopers are pretty resilient, but they'll cut through your armor and health with just a few swings of their batons. The general jist of the fight, though, will entail you sitting back while your sniper does his thing on the baddie. If it does get entangled in close-quarters combat with a commando or Tarfful, chuck an EC grenade at their feet to momentarily stun the foe, then start pelting it with blaster fire.
Note that the second bodyguard will almost always land in the same place when he jumps into the arena (which usually occurs immediately after the first one dies). If you plant an EC grenade just before he hits the ground, near the blaster ammo by the anti-armor position, you should be able to get a headstart on killing him thanks to the stun effect. If you have more than one grenade, chuck them all at his feet and he'll probably stay stunned long enough for you to kill him before he has a chance to move.
Obliterate The Outpost
Locate Trandoshan Compound
Breach Perimeter Defense
Walk down the path here until you come to the outer edge of the compound. There'll be a single soldier up in a tower overlooking the minefield here; regretfully, he's chosen to haul an explosive barrel into the tower for companionship, allowing you to destroy the entire tower with a single shot. After it goes up, task one of your soldiers with disabling the first mine, then back up. A whole horde of Trando berserkers will be coming for you soon. They'll trip their own mines, thankfully enough, but will still need to be taken out before they deal too much damage to your teammates.
Penetrate Outer Defenses
When the coast is clear, start working your way down the path towards the base. You'll come across some battle droid opposition, but nothing you shouldn't be able to handle easily. After you clear the trenches, you'll come to a sniper position; set up one of your teammates there, but stay back, as the rocket turret nearby will open fire. You'll want to edge yourself over behind the sniper and use your own sniper rifle to eliminate the turret gunner, then walk forward a bit to trigger another wave of berserkers.
There are actually three separate triggers here, if you follow the path laid down for you instead of jumping over them. The first is a barrage of grenades from over the wall, which are difficult to evade if you don't start moving backwards as soon as you spot the first one. The second will be a wave of three or four berserkers, while the third will trigger as you near the charge-placement spot across from the ramp leading up to the turret. If you just keep your teammates formed up on you during all of this, you should be able to survive quite handily, but if you wish, task one of them to the turret to cover you while another soldier sets the charge that'll get you inside.