I don't think it's what you suspect.
One tell-tale of a failed cooling unit is a yellow powder below it, usually near the burner. It's the sodium chromate anti-corrosion component of the coolant. It would never be liquid - the coolant is gaseous (ammonia + hydrogen) that evaporates almost instantly if it leaks (and leaves the yellow powder behind).
Not sure what that liquid might be, though. Especially along the gas line. Can't see it very clearly in that photo, but there should never be any liquid there. Is the condensate drain tube feeding to the outside as it should, or is it maybe dripping to the interior?