If the blood is coming from the ceca I don't think cecal worms would cause that much blood, and I base that on a couple of necropsies I did where if found cecal worms, but no blood (I have pictures if you are interested). Twice I have seen blood like that in mine, one was a young pullet, the other was a turkey poult. The pullet had coccidiosis, the poult had blackhead (histomoniasis). Blackhead is rare in chickens, but it does happen.
When I see funny eyes I just assume it's ocular Marek's and if I can get clear enough pictures I email them to a UC Davis pathologist to see what he says.