When you say "no hub connector" do you mean a rubber coupling with stainless worm drive hose clamps on the ends?
As to getting to it, I do not know enough about your floor plan exactly however is the vent piping going up the wall behind the shower faucet area? The black tank is usually under the toilet and there are only so many walls the roof vent pipe can go up in that area. If it is in the shower faucet wall there should be an access panel to get to the trap of the shower and the back of the faucet. If so then maybe you can reach the vent pipe.
Unless the bath and kitchen wall is thicker then normal for the pipe to run up that way.
Where is the pipe in location to your floor plan? I'm just looking at the 2001 brochure for the T2363 trying to figure out where it might be.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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