Rear dashcam through rear channel?

Am considering a rear or 3'rd camera for my dashcam. there is a channel at the top of the rear hatch but I cannot get a good look at it. Has anyone else tried to run cable through it? Is the part on the hatch itself accessable from the end of the rubber channel? Or does one have to run cable to the end of the tube coming out of it? (in other words can I get to cable in the rubber chanel within the red circle on the window side?



I simply cannot see what is on the other side of the rubber channel that goes from the interior roof to the top of the window

 

This was the best pic I could get of the inside... my endoscope went in the trash a few months ago. There is a tube coming out of the rubber fitting with wires in it. I am not sure if that tube is an extension, or if the tube can be accessed to pull wire through the end of it... You can barely make the tube out. I have to go to Toyota in the next few days and if no one can answer, I will see if they can talk to me.

 

Why would you want to? The rear camera sucks and any time it rains it is basically unusable. The soldering alone or wiring would be a headache and possibly cause problems.