Your army

Valdash recommends organizing the army as follows. Naturally he will re-organize things according to any plan that Lord Grim and his advisors have in mind.

Maneuver elements
Commando squad / free agents
Grim, Ug, Verschoyle and Zumm

Infantary unit (18)
1 sergeant (goblin 2nd-level warrior, Thurzar, or orc warrior)
13 or 14 goblin warriors

Artillery unit (2)
Infantary unit, but also armed with crossbows

Elite infantary unit (2)
Valdash or Kardash
10 goblin elite guards (4th-level warriors armed with halberds)

Ogre unit (1)
4 ogres

Ballista unit (1)
Light ballista
Gnoll siege engineer
Goblin blacksmith
4 goblin 1st-level warriors
1 min to set up or take down. While carrying the parts of the ballista, the team can move at its normal speed. While set up, the ballista can fire once every other round. It has 20 bolts.

Cavalry unit (1)
2 2nd-level goblin warriors riding worgs

Non-combatants
Tlagnak, goblin holy man (Valdash assumes he will stay out of combat and only attempt to heal people he can get to safely)
Zurga (Valdash assumes that since Zurga is a woman she will not be in combat. For her own part, Zurga is scared of combat but is confident that Verschoyle would keep her safe if she stuck with him.)
The battle-wagon (although the wagon itself is resilient, the horses are not trained for combat)

Infantary sergeants
Thurzar (2nd-level goblin rogue)
3 orc warriors
16 2nd-level goblin warriors (Valdash's 20 trainees, minus the two worg-riders, Skardash, and Thurzar)
Each of these sergeants commands a squad of 13 or 14 goblins. (Most squads have 14, but four of them only have 13.)

The army has enough crossbows to equip two of the infantary units with them. (That's 30 crossbows; there were some in Garduk.)

Valdash and Kardash will each take command of half of the Garduk elite guards.

All the units above can move at the same speed (30ft), except the worg-riders who are faster (50ft).

Valdash assumes that Grim and his assistants will not want to be tied down by directly commanding infantary units. They could of course take some of the army personnel with them, either collectively or each having an individual squad. Valdash will re-organize the rest of the army accordingly.