The official make-up of the Rebel Strike Team on Endor is inconsistent, so here is my guess...

Rebel Commanders
General Han Solo
Chewbacca
Princess Leia Organa
Major Bren Derlin

Rebel Forces
Captain Yutani - heavy weapons specialist
Orrimaarko - scout
Lieutenant Greeve - sharpshooter
Lieutenant Page - scout
Lieutenant Nik Sant - survival expert
Sergeant Junkin - demolitions expert
Sergeant Squalls - demolitions expert
Sergeant Bruckman - point man
Sergeant Brooks Carlson - pathfinder
Corporal Kensaric - tracker
Corporal Midge - marksman
Corporal Janse - sharpshooter
Corporal Delevar - medic
Corporal Beezer - technician
Black Trooper 1 (briefing)
Black Trooper 2
Black Trooper 3
Trooper 1 (seen in hangar)
Dresellian Commando (briefing)
C-3PO - protocol droid
R2-D2 - astromech droid

That gives us twenty commandos in total, including Derlin - 20 can fit in an Imperial shuttle.

Rebel Casualties

4 commandos killed during the first bunker raid
5 commandos return outside when they are captured and 6 more are captured outside... where have the other five gone?
It is reported that at least half of the commandos were killed in that battle, so I'll add at least 6 more to the death toll.

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If anyone can help with the five missing troops, then please comment!