The drainage holes under my hatch are plugged up. Thought about sticking a coat hanger with a slight bend at the end down them to clear them out. Is there any rubber tubing or anything at the bottom of the holes I should be worried about ruining?
I climbed under the car with a flashlight to try to find the other end but I didn't see anything and I don't want to just blindly shove a coat hanger down them until I know what is down there

 

it is rubber tubing that is used to drain the Hatch (also each corner of the sunroof)
Your idea should work.
I would get it wet though and start snaking it...(may be easier to unclog)

 

Awesome, will do! Thank you so much!

 

Try blowing it out with some air pressure , a bicycle pump will work.