If you would like a guide I can suggest one. However, it is a REALLY long video (close to 50 minutes) and I didn't actually see it. I just heard its good.
You are going to have to give us more information about your raid comp.
1) How many melee do you have . If you have at least 1-3, you are golden.
2) Do you have a rogue or paladin. Rogue is more important than a paladin since not all paladins have good enough reaction times.
3) Again, how many melee / ranged do you have?
This fight is actually incredibly easy as a monk healer because you get targeted by 0 mechanics. As in, frostbite (empowered or not) and sand trap. You might not think this is important, but because the game registers you as a "melee" person, you can stand there and be safe.
Similar to normal, all dps should start on Sul with cleaves on Malak. Sul should be in the range of 40-50% for a first kill by the time you push Malak. If you have a ton of excess time on dark power then delay hitting Malak and focus more dps onto Sul. Lust + cooldowns at the start.
Priestess is empowered next. Ranged groups stay max range. Melee group stays in melee. When twisted fate goes out, each group kills their own roughly at the same time. Both groups should stun + slow their add right when they spawn.
Assuming you only had 2 loa spirits in the first malak empower, you should get at maximum 3 twisted fates. If you waited really long in dark power and a 3rd spirit spawned, only two fates will get off. Ideally you push her between fate 2 and 3. Sul should be at 10%.
At this point kazrajin is empowerd. Tanks can honestly finish Sul. Tell your group to not go crazy on kazrajin. Healing cooldowns need to be rotated here.
Afterwards, it goes back to priestess. At this point we move all the bosses to the wall. This is because of all the sand that is leftover in the middle. Same deal here. Dont push too fast. Try to get malak / kazra as low as possible so that you push right at dark power.
Malak is empowered next. Time this correctly such that an OLD type of frostbite (biting cold I believe is the name) is put out WHILE priestess is empowered. Thus, he won't do his deadly frostbite until 30-40 seconds into the phase. Remember, the empowered ability is on the same cooldown as the normal ability. That is pretty crucial to remember. This is also the reason why at the start, if you let 3 loa spirits spawn, she will only do 2 twisted fates before you push priestess empower #1.
Most important things:
1) Malak empowered should at maximum throw out 2 empowered frostbites. If you time it right the second time he gets empowered, he will only have 1. If your rogue smoke bombs two seconds before the timer goes off, he will NOT put out the empowered frostbite. This makes things a ton easier.
Additionally, if you have a paladin in your raid, this person MUST be looking out on the actual field (not raid frames) for a tiny blue arrow that goes over a person's head BEFORE they get frostbite. If you HoP within the 1-1.5 second window you have on that person before the debuff goes out, they will not get it. Of course, this requires your paladin to be paying a ton of attention and your ranged / healers (not you) to be close when a frostbite is about to go out so that they can see the blue arrow (DBM WILL NOT TELL YOU NOR WILL RAID FRAMES).
2) you are bound to get one empowered frostbite going out.
If this person does not stack properly they will take 300k per second. If they stack with 1 person, they split 180k per second (pretty much worse than the 300k but it is on 2 people so its not awful - still not recommended). If they stack with 2 people the collective group of 3 takes a minor amount of 60k per second.
Because the melee / tanks / you are never targeted by sand traps and NEVER have to move (don't move for kazra'jin roll) you have to form 2-3 groups within melee that consist of 2 people each that are tightly stacked up.
Your 2 tanks = 1 group.
You + 1 more melee = 1 more group.
If you possess even 1 more melee or 2, then this = a 3rd group.
You form a triangle around the boss and never move while malak is empowered. The person who gets frostbite MUST realize they have a 1-1.5 second window where they know its them since they will get that blue arrow above them. They immediately run into one of these groups. After 6 (if 3 groups) - 8 (if 2 groups) seconds, they swap to another group. If you swap early, you will wipe probably because you cannot stay at one group for more than 8 seconds.
Frostbite lasts 30 seconds. You can stay at a maximum of 8 seconds in one group. You cannot return to that group for 8 seconds. As you can see, it becomes so much easier if you have 3 groups as a result.
Positioning is key here. Once you get it down you will probably find that you prefer healing through an empowered frostbite as opposed to the normal frostbite.