Need to look harder.

[serpa4]

I'm putting my marine head back in and pulling the urine diverting toilet out. Things have changed under the sink. I have an inverter, autopilot controller, pump, solar charger, and other things the previous owner installed. All done neatly, but not sure if he covered or pulled the vent..
I cannot find where the toilet vent goes in my Venture 26.
Anyone know where the toilet vents?