Watching as Wash goes down, Alton panics and rushes over to his side, "No no no no no! I wish Yinra was still here." Placing a hand on Wash's shoulder he kind of sings, "Life's going nowhere, some healing for you , yeah you're staying alive, staying alive." Once that is done, Alton places himself in front of Wash and looks around for Balassar. Finding him on the ground in the tunnel he panics again and kind of sings, "You got knocked down, but you'll get up again. There never going to keep you down."

Movement: Up 15ft to Wash then up 10ft to be in front of Wash to see down the tunnel
Action: Casts Cure Wounds on Wash for 11 healing
Bonus Action: Casts Healing Word on Balassar for 7 healing

(OOC:  Sorry, if you cast two spells on the same turn, one of them has to be a cantrip.   Are you healing Wash even if he's not down?)

(OOC:  Also, liking the musical heals very much! :) )

(OOC: Could Alton using a healing potion on Wash if he is down and cast a spell?)

(OOC:  No, it's a bonus action to drink a potion for yourself, but a full action to feed it to someone else.)

Wash doesn’t have shield, so is definitely down.

(OOC: Okay, so Alton will do pretty much the same stuff but instead of casting Cure Wounds on Wash he will administer a health potion to Wash. If that works.)

That does work.  So Wash, you are up.  If it's okay, I'll roll the health potion:  8.

Sorry.

So Wash, you are prone with 5HP and Balassar, with 7HP, but you are both conscious.

Wash is happy to be up again. He thanks Alton "I owe you one friend", stands up, releases a heavenly blast at the duergar Attack: 21 Damage: 7. He then uses a a bonus action healing light to heal Balassar another 6 hp, and uses his remaining movement to run 15 ft Nth.

The duergar staggers against the impact of the blast, stumbles, drops to one knee, and then falls; his body shrinks back down to its previous size.

And the course of the battle seems to have turned.

Balassar is up.  You are prone but conscious with 13 HP.  You can see that there is a third kobold lurking back to the south.

[I think Alton moved 25 ft and I don’t want to be blocking him (just trying to get some distance).]

(Corrected below)

Balassar stands up and looks down at the two Kobolds and lets out a roar as he swings at one with his sword.

OOC:

Standup

Attack: 23 Damage: 7

Kobold 3 gives a squeak of surprise as what it had believed was a dead body stands up and stabs through its heart.  It falls to the ground, quite dead.

Kobold 5 drops its hand crossbow and draws its scimitar; it comes up to flank Kobold 4, and attacks Balassar:

Attack: 25 Damage: 10

As Balassar drops unconscious to the ground, he hears one kobold say to the other in draconic:  We need to get out of here, or we're dead!  Both kobolds run off along the corridor.

Wash, Balassar and Alton are up.  Balassar, you can again wait until the others have taken their turns, in case they get you up before you need to make a death saving throw.

Alton hurries over to Balassar and administers a healing potion. Looking around he spots the small room that the duergar was hiding in and says, "Do you think we should hold up in there for a little bit?"

Balassar gets healed for 4

Balassar and Wash are up.  We're still in initiative, but if you are going to let the two kobolds flee, combat will end.

Balassar just looks at the two kobolds with rage in his eye as he charges for them swinging at the closes one. He will then let out another roar as he brings his blade down again.

OOC:

Move 30 ft

Attack: 19 Damage: 9

Bonus action: Action Surge to attack the same one unless it has died then he will attack the other.

Attack: 13 Damage: 6

Wash moves back towards the others his full movement and releases a heavenly blast at any remaining foe. Attack: 18 Damage: 8

Splat and splat.  Both remaining kobolds are dead.  

In addition to the five kobold and one duergar body that now litter the floor, you have time to see what else you have uncovered.

There is a large space to the south that appears to be lots of beds, probably for kobolds.  There's a passage leading east from here.
There's a chamber with some beds to the north-east, and what looks like a closed door to another chamber.
There's the smithy where Alton is currently standing.
There's the blacksmith's chamber to the south-west,  where the duergar emerged from after he had enlarged his body somehow.

Let me know where you want to go, and what you want to do.