I'm moderately confident that this will turn out to be the right thing to do and will turn out OK. I don't know if they still do, but Forestry Tas used to pond blue gum in salt water for use as keels- now they didn't do that to have it dry did they? Wilson Bros used to build those big sailing barges in about a year. The first job being to fell a tree for the keel. How dry is an 18" x 18" keel going to be in 12 months? They also planked green, but promoted a moderate amount of airdrying in the (much smaller dimensioned) planking by hanging every second plank and then planking the gaps. (Good spilers those boys). All this is documented with photographs and interviews with old timers in Gary Kerr's book.
I have a friend who built a fifty foot fishing boat about 30 years ago in Bernard Wilson's yard. He said Bernard told him to build the keel and deadwood wet and never let it dry out. Now this one has dried out, but from my experience a dry piece of blue gum will return to its original dimension, or very close, upon immersion.