There was at least one thread sometime ago about using wood stabilizers. Most of the discussion was about how to use them to speed up the curing process for green sticks. They are also often used for firming up wood blanks for pen turning, or knife handle scales. CAS, who hasn't posted in some time, bought sone Pentacryl. Its pricey, but has a good reputation. As I recall, it takes only about 6 mo. to cure the wood. There are several other options.
I had some stuff called Turner's Choice wood stabilizer from CedarCide. It was very aggressive pushing water out of green sticks. It has silicones in it, and purports to do a rapid "fossilization" of the wood. Some months ago I had a piece of spalted soft maple that I thought might make a nice T-top stick handle. Spalting, a form of fungus rot, had made the wood rather mushy. I immersed the carved handle in the solution for about 2 weeks till there was no more air being displaced. (Some people make vacuum chambers to speed the process to an hour.) The resulting wood was firm, somewhat waxy to the feel, and a little darker than at the start. The down side was that it reeked of cedar. I've let it sit on a shelf for a few months, and the odor has finally dropped to where it is not overwhelming.
Considering you have cedar to harden, that stuff might work well for you.
A few weeks ago I found that my elderly uncle had done a poor job maintaining a window casement, and that water has seeped in and started rotting the base of the frame away. (Guess what, Duck tape does not block water as well as a sealing caulk!) I stabilized it w. Elmer's rotted wood repair glue. It dries hard and clear, but rather shiny, and makes the wood look almost wet. I've since read that a similar product from Minwax works a little better, because it seeps farther into the surface. The pics I've seen show that it also makes the wood look damp, and darker.