I attacked one stronghold just to milk some gorg for my upgrade...i didnt defeat it. And when I'm seeing again how much loot jus available its showing wrong info of available loot in the description but it's good evoke scouting... Here you go. Not so important but i thought of sharing!
It is correct. The amount shown at map pop up is max amount you can plunder and the amount show at stronghold's island is the loot remaining