In the Co-op mode, only one road to the Guardian Order is generated, and usually, it's for the blue player.
Only one road to the Guardian Order or 2 roads for the blue player can be generated if you create a single-player game against the AI.
Once out of 20, it generated an impassable block in the Dungeon, where the Monolith's guard blocked the path further (but this is a technical issue).