Gideon Argus has the "Command" special ability: (Action) 2 Strain: Choose another friendly figure within 3 spaces. That figure may interrupt to either perform 1 move or 1 attack.

If Gideon uses this ability on a fellow Hero, can that hero use a special ability (e.g., "Charge", etc.)?

It isn't clear to me, or maybe I'm over thinking it... The answer is probably "yes" and I'm over thinking it.

No. He can attack or move using the basic rulebook actions. They cannot make special attacks.

What Hida said. It's the same with any other unit that grants extra attacks or moves. If it doesn't say yuo get an extra activation, you get just what's listed. The wookiee can't charge, the nexu can't pounce, Darth Vader can't use Brutality.