All three fail and now have the Blinded condition. 

Reminder of order. Renee, you're up!

Round 1 Initiative Order:
Heilamin
Mackenzie
Renee
Cloak 5/6 Frightened
Werejaguar Blinded
Cloak 7/8 Frightened
Cloak 9/10 Blinded
Brazzak
Cloak 3/4 Frightened
Cloak 1/2 Frightened

Renee moves up and attacks the werejaguar. 

Attack: 21 Damage: 6 Sneak attack damage: 19

Bonus action to Disengage and stand next to Mackenzie. 

Cloaks 5-8 cannot move, they are frightened by the presence of Mackenzie. They stay put. 

Werejaguar will move forward and attack Mackenize with disadvantage because of being blinded. Mackenzie, roll your polemaster reaction attack! 

Werejaguar: Bite Attack: 21 Damage: 8
Werejaguar: Claw Attack: 14 Damage: 6
Werejaguar: Claw Attack: 15 Damage: 5

Cloak 9/10 will do the same at disadvantage because of being blinded. 

Cloak 9 Attack: 5 Damage: 8
Cloak 9 Attack: 8 Damage: 5
Cloak 10 Attack: 20 Damage: 3
Cloak 10 Attack: 6 Damage: 7

(Forgot disadvantage, but didn't matter all missed!)

Brazzak, you're move. 

Snapping to order, the dragonborn soldier immediately picks out the werejaguar. Brazzak charges and unleashes.

Attack: 10 Damage: 7

As the Werejaguar closes, Mackenzie takes the opportunity to thrust at it, but its erratic movements cause the strike to hit nothing but air.

OOC: With shield of faith Mackenzie's AC is currently 20 so amidst the chaos none of the attackers manages to score a telling hit against his armor.

OOC: I think that those that are frightened do get to make a saving throw at the end of each turn, so just to confirm will that saving throw be made at the end of their turn in round 1 or not until round 2?

You are correct. I will roll all of those saves.

Cloaks 1-4 are unable to move. Here are saving throws for all of the cloaks and werejaguar to break either Blindess or Frightened. 

Werejaguar CON save: 4
Cloak 9/10 CON save:  4

Cloak 1/2 WIS save: 20
Cloak 3/4 WIS save: 20
Cloak 5/6 WIS save: 19
Cloak 7/8 WIS save: 20

The werejaguar and Cloak 9/10 are still blinded, but the other cultists are no longer frightened. Heilamin and Mackenize, you're up!

Heilamin moves up and casts Thunderwave at 3rd Level in order to catch the Werejaguar and Cultists 3, 4, 5, and 6. (Spell Save DC 15)

With his bonus action, he will inspire Brazzak (to Friends in Low Places by Garth Brooks): "You've got friends in low places, where the cultists frowns and the fear chases your blues away! And you'll be okay. You're not big on social graces, think we'll slip on down to the secret Oasis, Oh, you've got friends in low places." 3 Brazzak you can add this to a roll of your choice.

"I dunno who Social Grace is, but based on the song I think I'd like ta meet her sumday!"

Reroll for round 1 Reaction attack for advantage due to jaguars blindness if allowed 24 - Damage was 7 if hits and ruled in

As the cultists shake off their fear [damn] Mackenzie exclaims "Fanatics are the worst kind" just before the booming wave of thunder hits the group in front of him, then seeking to take advantage of the jaguars blindness charges ahead to engage, and makes the most of the situation with all the attacks landing, and with each Mackenzie draws in divine power and releases it with each connection (all hits smite @ Lvl 2)

Attack 1: 19    Damage: 7

Attack 2: 15    Damage: 13

Attack 3 (Bonus Action): 25    Damage: 11

With all of these hitting Mackenzie is going to go to town on Smiting

Attack 1 (smite L2) smite damage: 29 (Critical Hit)

Attack 2 (smite L2) smite damage: 10

Attack 3 (smitel2) smite damage: 13

If the jaguar falls on 2nd attack then the 3rd will be against the one of the blinded cultists (Great Weapon Master), but note that if the attack is against the jaguar the weapon damage is reduced to from 11 to 7

Above may be confusing so have summarised on Discord

(I didn't update positioning, but you'll be able to hit werejaguar, 9 and 10.) CON saves for thunder wave to take: 6

Werejaguar: 4

Cloak 9/10: 11

The two cultists and werejaguar take the damage. 

Mackenzie you raise your weapon and smack the werejaguar twice, critically hitting with your first smack. With the massive radiant damage that emits from your weapon, you demolish this werejaguar. You then bash one of the blinded cultists with your last attack. With that attack he is barely standing, on death's door. 

Renee attacks the cultist in front of here. 

Attack: 10 Damage: 10 Sneak attack: 11

Renee easily puts down the cultist. She seems startled by the blood that spews from the cultist as they fall to the ground in front of her. 

The cultist no longer frightened by Mackenzie move up ranks and attack, 5/6 move to attack Heilamin. 7 moves to attack mackenzie, 8 moves to attack Renee. 9 is still blinded but swipes at Mackenzie also. 

Cloak 5 Attack: 14 Damage: 3
Cloak 5 Attack: 23 Damage: 3

Cloak 6 Attack: 20 Damage: 4
Cloak 6 Attack: 13 Damage: 5

Cloak 7 Attack: 16 Damage: 7
Cloak 7 Attack: 9 Damage: 5

Cloak 8 Attack: 15 Damage: 6
Cloak 8 Attack: 18 Damage: 7

Cloak 9 Attack: 8 Damage: 3
Cloak 9 Attack: 17 Damage: 8

Brazzak, you're move!

Heartened by the musical inspiration, the soldier unloads on the Werejaguar!

(Werejaguar is dead, I will move these attacks to the closest cultists.) 

Brazzak your first attacks miss (even if you would add the bardic inspiration from Heilamin), but you next attack hits killing cloak 9 and you severely wound cloak 7.