I found what looks like the same corrugated pipe installed in the galley sink drain on our p31-2. It was clamped to a short section of PVC pipe which was screwed into the seacock. Hard to believe.
It looks like you have a standard pump out deck plate fitting. Replacing the hose should be straight forward.
We re-plumbed the entire waste system with Trident sanitation hose according to Peg Hall's recommendation.