(Are we now at Grum and Bartholomew's initiative step?  If so...)

Grum will spring forward and move quickly (movement speed, but not dashing) towards the further room the goblin dashed into, making use of any cover available. (In terms of game mechanics, I'm assuming the room is further than 30ft away from Grum.  If so, Grum will use his full 30ft movement and end up taking shelter behind one of the low fieldstone walls if there's one available.)  Then Grum will draw his bow and Ready his attack to release as soon as he gets any kind of decent sight of an enemy.

(If the room is less than 30ft away, Grum will take cover beside the doorway and take a look in, and see what he can see before using his action.)

(Would i have an opportunity attack?)

(Unfortunately it did disengage as a bonus action last turn since goblins can do that, but I should have commented that before sorry. Also yes Initiative order still active unless you guys back off or try something else)

Unfortunately the bugbear is not fooled by Squelch's impersonation. "You are not Gork! Impersonator!"

The room was about 20ft from where the initial combat happened, so you are able to peek in, Grum. The room contains sacks and crates of looted provisions piled up on the far side towards the back of the room and in the middle of the room the coals of a large fire smolder. You aren't able to see the goblins or Klarg at first glance, but you can make a perception check to try and locate them (would take an action-- search)

Grum will Search, then.

Perception: 19

Seeing this, Grum also switches from his bow to shortswords in anticipation of fighting up close in the next room. 

On her turn, Callie immediately attempts to quiet her footsteps and keep out of the next room's line of sight. Though she knows she'll probably be seen if someone comes through the tunnel, the chance to possibly take the bugbear and goblin off guard is one that she isn't keen to pass up. She keeps her shortbow at the ready.

Stealth: 22

(Mechanics-wise, Callie will get out of view of any onlookers from the next room and find a spot overlooking the entrance)

The goblin that Callie heavily wounded is near the crates at the back of the room, clutching it's leg and looking winded. You see two goblins on the right of that goblin, attempting to hide behind the crates but you can see them pretty clearly. You don't see Klarg, but you see his Wolf, Ripper, that Yeemik had mentioned previously kind of crouching behind a stalagmite about 10ft away from the door, it's stench betraying it's position.

<Squelch> holds his position. <Brandor's voice> "Should've bargained with us when ye had the chance gobby." 

Followed by <sounds of a chicken clucking>

Make an intimidation check :)

Intimidation: 14

"Glurg! Shoot whoever that traitor goblin is when they come in. Klarg will build a shrine from their bones!"

"Oooo I think I hear Klarg the coward in there? Couldn't fight his own battles so he bossed a bunch of gobby's and his pup to do it for him!" Brandor called out into the cave. "Come'n out here an' fight me on yer own. Or is ol' Klarg too scared to fight a dwarf!" He was laying it on pretty thick so he hoped the brute would come out thoroughly insulted. 

(if this counts as my turn, taking dodge again as I move forward almost to Callie's position doing my best to not reveal her)

DM:

(I'd say intimidation since it's trying to goad him into attacking)

???: 1

(Lel)

"Hey **** you! Cragmaws, with me!"

You hear the trudging of footsteps and snarling approaching the entrance, and you all ready yourselves preparing for an attack!

Please roll initiative for this new fight :)

Grum initiative: 5 

Goblins: 4

From the last comment:

Klarg: 14

Ripper: 20

(Does Grum at least see him at this point?) 

(He's still coming out so after initiative is all rolled he will appear)

Initiative: 12

When it is my turn, I will attack any enemies with Eldritch Blast, or, if there are no enemies visible, will hold my action until one becomes visible.

Attack: 14 Damage: 2