Intimidating a bloodied enemy into surrendering is a Standard Action, normally, and requires an actual Intimidate roll.
To save time, I've rolled Intimidate for you, and have given you a circumstance modifier equal to the number of allies nearby.
1d20(14)+5=19
Unfortunately, this isn't quite enough to Intimidate him into surrendering.
Oh, and good job remembering I allowed everyone to know extra languages equal to Int mod. If everyone who is gaining new languages could put them on their sheet, that'd be appreciated. Also, feel free to justify it how you want, whether you're picking up memories from a long dead adventurer or you knew the language all along, it doesn't really matter in this cave.

The kobold seems to be hyperventilating as it grips the back wall, its eyes shifting rapidly from one enemy to the next. It settles its gaze on Gerand, lowers its spear... and spits on the ground in front of the Swordmage.
In Draconic, it says, "
It does not matter whether you kill me here or not. In the end, the Dragon Below will devour you all! Praise the Dragon Below! Praise Khyb--"
The kobold is cut off as an arrow appears in its chest. It drops to its knees as the same screech as before sounds off, and then falls to the ground.
Combat over! Victory is your's!With the kobolds in the cavern defeated and their leader (the disturbing creature Ironteeth) slain, Winterhaven's kobold infestation is over, though new questions remain. Looting the bodies yields 12 gp and 48 sp, along with the weapons and armor worn by the creatures, though most of the armor is fitted for small creatures. Ironteeth has a small pouch in his possession, containing a silver key and a scroll of parchment written in common.
The message reads as follows:
My spy in Winterhaven suggests we keep an eye out for visitors to the area.
It probably does not matter. In a few more days, I’ll completely open the rift.
Then Winterhaven’s people will serve as food for those Lord Orcus sends to do my bidding.
-Kalarel
There is also a fairly large chest in the northeast corner of the cavern.