Strong smell of fuel does suggest a leak in the exhaust.
But I would concentrate more on the exhaust manifold and manifold gasket, rather than the cat. Because the cat is after the upstream oxygen sensor and a leak there would influence only the downstream sensor.
I do not think there's a wire broken from the front oxygen sensor. That would trigger other fault codes. All the ecu is saying is: I am seeing a signal from the front sensor (not a short circuit), but it is always lean and not switching to rich.