Don't waste your money at a mechanic anyway, this is all troubleshooting you can easily do yourself.
Check for water in your fuel rail by turning your ignition switch "on" so the fuel pump pressurizes up. Go to the schraeder valve/fitting on your fuel rail and bleed off some of what comes out into a cup. You don't need much, maybe a few teaspoons full. Go to an open area in your yard and pour it on the corner of a paper towel, then see if you can get it to burn by lighting it with a match or lighter. If its fuel, even old bad fuel, it will easily catch and burn. If its water though like I suspect, no fire in the world will light it.
My reasoning is simple, whatever is being squirted into the cylinders is not burning even though you have ample spark. This is proven because starting fluid gets the engine to fire up, so the only thing missing in the whole equation and preventing the engine from starting is fuel. You're saying that when you inspect the cylinder by removing the spark plug the cylinder interior looks wet. It shouldn't look like that, it should be bone dry. Gas would evaporate, water wouldn't. Gas would ignite, water wont.