I’m not sure about rejuvenation. Some folks say that boiled linseed oil rejuvenates wood. It may be worth a try unless someone comes up with a sure fire method.
I worked on seats today. Pulling the splines has always been difficult for me, but what I’ve found is that Acetone will soften the glue. I’m not saying it comes out clean, but much better than without. You’ll need some small width prying tools and scrapers to get the glue and stuck canes out of the groove.
I apply the acetone with a small plastic syringe. Load it up....a couple of times. Cover it to slow down evaporation and try to pry them up after a couple of hours.
A narrow brass wire brush helps clean the softened glue out, too.