I think way too much is being made of this. DCS implies tissue damage. Anytime there is tissue damage (get punched, fall and skin your knee, bang into the swim platform, etc.) there are going to be a released inflammatory mediators, some of which happen to be participants in immune responses. The body does this to clean up the detritus of the tissue injury. If DCS were truly an immune response there would be antibodies left over, and if there were residual antibodies, one would be able to study them to see what they were in response to.
If there are double blind, peer reviewed studies proving the benefit of taking NSAIDS to prevent DCS, great, take them, but don't get tongue tied arguing the terms "inflammatory" and "immune" as if there is some revelation in the exercise. The body is just trying to heal itself.