Water travels in some unexpected ways. I've done some extensive delamination repairs, and one thing I can tell you is that if you are seeing delamination, water got in there.
There are many threads here talking about how to remedy the delamination. It's a bit of a process, but if it hasn't gotten too bad, repairing it now shouldn't be too difficult.
Regardless of the repair, you definitely will want to stop the water intrusion, having ripped apart several delamination issues now, I have found the visible area to generally be the tip of the iceberg.
I highly recommend Eternabond tape for seams. I use Sikaflex 505UV for my lap joints; it holds up far better than Dicor in my experience.