We have a t139, same trailer, but metal skin, so no demamination. It did have soft spots around one area under the window, so water damage of rotting wood. We knew about it when we bought it and planned to fix it, because the price was very reasonable.
We re-sealed every seam and penetration on the camper, then repaired the wood from the inside. We removed the interior thin wood wall covering that was over the soft spots, and cut out the rotten framing. We replaced it with the same size wood, epoxied, screwed and tonailed into place. Then cut a piece of very thin wood to fit and fill the wallboard we had removed. Wood filler and a good sanding gave a nice smooth surface to cover with vinyl grasscloth wallpaper. The repaired area is firm and strong, and looks very nice If I say so myself.
In our hot, dry climate, we see a lot of delamination. An rv dealer told me heat can cause it as well as water.
I don't know much about delaminaion, but maybe if you just fix the leaks, you can live with the bubbles, if the framework is sound. Or maybe you can get the panel replaced without unreasonable cost.
I like our camper so much, I felt a little sick when we realized it was more extensive than we first thought, so I understand how you must feel! Good luck!