Personally, I would never recommend using wet wood for pens. If they had any wild grain, or a knot, it will definitely crack. A blank is very easy to dry. If you cut it down to 1" square x 6" long it will dry in no time. Some guys use a dehydrator, I put my blanks on the furnace trunk line this time of year. Blanks on the furnace duct will dry in about 3 weeks, and that's more than 100 blanks. If I'm really in a hurry, I take the blank and also cut it to a rough length. I put it in the microwave and give it short 30 to 40 second sessions. Let it cool between and in less than a hour you have a blank ready to go.
Rich