I'm having the EXACT same problem! The mission is there but R3 doesn't show blue to indicate the mission there.

On my map it shows the mission, I can click on the guy but, when i try to bring the hay and exit there's no cut scene and the sheep don't eat the hay. I go to click the Odin R3 thing and nothing highlights blue but, I can click the guy and it does the "haven't found it yet" dialogue. In most cases it's an easy fix doing the animus thing but in those cases everything turns blue, plus I've killed the sheep and nothing happens. I've redownloaded the game, I did the animus trick and nothing works. I've almost platinumed the game, this is a problem.

I'm having the EXACT same problem! The mission is there but R3 doesn't show blue to indicate the mission there.