From the comref:
CreateUnittype createUnit unitInfo"Format of unitInfo is: [pos (Position),group (Group), init (String), skill (Number), rank (String)] Note: init, skill, and rank are optional"
Backoff November 01, 2002, 08:12
The Group parameter MUST be an existing group or the unit won't be created.
To create a unit, you must first have a reference to an existing group. You cannot create new groups; this group must already exist at the beginning of this mission.
The easiest way to do this is to place a soldier in the editor, probability of presence = 0, and in his init field put something like "Spawn_group = group this"
In your script put
"JAM_EBOfficer" createUnit [getmarkerpos "rus1"
, Spawn_group ]