Mine (Cal 34) comes out and tees into the galley
line under the sink, try tracing that line to see if yours does, there may be a shutoff valve at the connection which could make it seem clogged. You are probably looking at a lot of ancient insulation
foam obscuring the line? Have you tried pouring some hot water
through to relieve a clog? This with some pressure from a plumber's helper works pretty well on any clogged drain. Also if you try this don't melt your plumber's helper like my ex once did.