Obviously the chances of Seattle converting on fourth down had to be pretty slim. I don't know what the NFL numbers show, but fourth and 10 or greater can't be great.
But a field goal by the Packers wouldn't kill Seattle, down five. If they turn it over on downs at wherever they were at (35?), Green Bay is really almost in field goal range anyway. Plus, the short field takes the deep throws like the one to Adams really almost off the board. It's easier to defend a short field.
My instinct at the time was to punt, but I can see good arguments in favor of going for it (including keeping the ball from Rodgers).