Playing Solo: Can not progress because not subscribed to online service. (PSN+)

I know I'm probably in the minority with this issue. Still, I can not progress any further in the game and unlock the challenges in Brickswich because the next "Mission Challenges" involve connecting with people and playing challenges in co-op. I don't have PSN+ because I don't play multiplayer games, so it's a waste of money for me. Is there a way to circumvent this so I can at least progress to the next challenges? I do not want to pay $24.99 to complete a simple mission in a free-to-play game. That's ridiculous.