You may finally resolve the situation with Carlos and his mine. It shouldn't come as a big surprise that you must order him to get here. Click on an area near your position. After that, order him to proceed towards the main gate (screen). Wait patiently for him to get here. Sadly, the gate isn't going to be destroyed. You won't find out exactly what has happened. Instead, you will have to wait for the game to grant you with an updated challenge.
New objective: Move Around The Back Of The Hacienda
The road which leads to the back of the hacienda can be found to your right. You won't encounter any enemy troops there. You'll only have to climb up several times. Eventually you will end up standing on top of a large hill. You'll have an excellent view at the hacienda from here.
You've got two choices here. I've already said that you would be allowed to sneak your way into the hacienda. If you want to stay out of sight for as long as it takes, you will only have to kill a single enemy soldier. He will be standing beneath you (screen).
I wouldn't recommend choosing a silent approach, because eventually you would have to reveal your position to enemy soldiers. As a result, it would be better to kill most of them from here. This will raise an alarm, however you shouldn't have any problems neutralizing enemy units. Additionally, your colleagues may provide you with much needed assistance.
You should stay here a little while longer, especially if you've decided to take on a more direct approach. Keep firing at the enemy units. Make sure you've disabled all vehicles by shooting at the gunners. You should also notice that some of your opponents will use nearby objects for cover. Wait for them to reveal their positions, so you won't have to waste more bullets trying to kill them. Secure this entire area before moving on towards the compound.
New objective: Infiltrate The Hacienda Compound
Once you're ready, approach the rappel icon and press the action key in order to slide down on the rope. Obviously you should wait for other members of your team to join you. Start moving towards your current destination.