Isabella's discovery gold bonus

Seven Cities of Gold: Gain 300 Gold every time you discover a Natural Wonder. This is doubled if the Natural Wonder is in Distant Lands.

i got a 300 gold bonus for the Natural Wonder next to my starting location, but i haven't received any for wonders i found later in the game. perhaps the game is only awarding the bonus if you are first to discover the Natural Wonder? when you find one, the game log notifications do say "discover" so this isn't just a terminology mismatch (like "settlement vs city" or "support vs accept").