I suggested pressure washing UNDER the engine where the leak was seen in filth but there is nothing under the hood that can't handle water or if there is, I'd want to know about it now instead of stranded on the road. Remember, vehicles operate OUTSIDE. Of course you don't put the tip of the 1500psi washer right on anything but 12-18" is not a problem.

I just reviewed the new pics and if it is not under the intake manifold (no answer on the smell question...) then the o'rings on the front coolant manifold (where the top radiator and heater hose attach) is more suspect. It will typically only leak under pressure and bleed and stop once the engine is off. It took me a while to find it on mine and if vehicle is used for short trips only, it may not show the leak until a longer trip is taken.