I have not had this issue with my Liberty, but, My Dodge Caravan did. My 2007 Liberty looks to have the same design. My Liberty has a short piece of hose bent ninety degrees on the A/C drain spigot.
My Caravan has a drain spigot on the firewall so condensation can escape to the outside. My floor was wet inside and the dealer told me the hose was plugged & fixed it for $300. The problem returned so i had to fix it myself. When I ran the engine with A/C on, water would gurgle out the spigot, and there seemed to be such high air pressure in the engine compartment, the water would blow back onto the spigot and run down the firewall. I fixed the problem by buying $20 of misc plumbing parts that I assembled to drain the water into the air that runs under the vehicle. I got a rubber elbow that I slipped on the spigot, an eight inch piece of hose, a pipe fitting with stainless mesh so insects couldn't crawl up, and another length of hose I tie wrapped to the suspension mount. Floor has been dry for several weeks with A/C on and record high humidity.