Assuming, Mark relays this question Erix suggests to Mome to show the spear to the Orcs, hoping that might be seens as proof of them both being gone.

Elero will agree with this plan, since he's following the convo via the Helm now.

Mark allows the staff to be shown, but asks that we keep it at a distance. 

Mome steps out of the shadows to yell "Hey ya!!" and jab the spear up in the air for everyone to see. She otherwise stays back and silent. 

The orcs all stand there looking shocked up at the group brandishing the Spear. Garund, on the other hand, turns to her sister smiling "Well, it seems you brought a strike force with you Rhodvil. I would have never expected my peaceful sister to travel halfway across Khorvaire with a group of mercenaries to kill my bosses and retrieve me. Well sister? You have the uppoer hand, what would you have me order this tribe to do?" Garund looks at Rhodvil, who in turn looks at you, seeming slightly confused and out of her element.

"I think we should enlist their help in rescuing our target and cleaning out the rest of this mess," Elero offers.

"I agree. With the help of locals, perhaps we can end this without more bloodshed."

So who’s going to ask the orcs to surrender?

Mome steps out of the shadows and walks towards the gathering, her head head high and holding the spear up. She attempts to Persuade (13) the orcs to surrender and to tell the group about Anric (Persuade 6). 

Zoveldra attempts to move closer to the orcs stealthily as they are distracted by Mome, ready to intervene if they attack her.

Stealth: 10 (or 24 if advantage from their attention being on Mome)

Mark will echo the sentiment, "We don't want you to have the same fate as your Warchief. You both look like fine Orcs, and you now have a chance for freedom. To really create a life that YOU want and not one that some creepy guy with a stick demands of you. Please relax and let's just have a conversation."

Garund looks from Mome carrying the Spear to Mark and nods "You speak truth, and have proven yourselves as worthy of command through combat. These orcs will listen to you and stand down." Garund turns to the other orcs and tells them what you've said, embellishing a little bit to make you all sound a bit more bloodthirsty than you actually are. The orcs don't like it at first, but eventually back down. They all take a step back, you've successfully deescalated the situation and the outpost of Velkynvelve is now no longer hostile. 

Garund looks at you all, "Well, because you all killed the last War Chief, you are technically the one giving orders around here. What to you all need from us?"

Erix steps forward aswell to join the conversation

"First of all, we would like to know where Anric is, the Dragonmarked you kidnapped. Secondly, how much do you know of the plan of those inspired?" he asks, his dragonmark is visible as he isn't actively trying to hide it.