Last I checked Myron Mixon uses the freshest peach he can. I've used pear cut off the tree that morning and cooked for the food editor/restaurant critic for the St. Louis Post Dispatch that afternoon. That guy has a seriously good palette. He didn't notice a difference.I will say that it took a little longer to smoke, being wet, but otherwise it was fine.
The notion that wood has to be dried out is a false one. We assume that, because by the time we get all our smoke wood it's already dried. Doesn't mean it has to be.
Don't sweat using the fresh wood this weekend.