Shower leaking in garage

[streetneons]

House built in 2005 in Florida. Shower was running, and I was in garage, the bathroom is on the other side of the wall basically. And it was dripping water onto the garage floor. I dried off the area, and ran the shower head and filled a 5 gallon bucket a few times and drained in sink, no leaks. I filled the bucket with water from sink later on and poured water into shower and it leaked in the garage again. The shower is a walk in shower and the material is a plastic like material. I believe the shower drain seal is the issue. How can I fix this.

 

[johnjh2o]

Can you get to the bottom of the shower or are you on a slab?

 

[streetneons]

I am on a slab. And I wanted to verify the leak location so I used red dye water, and it has a slow leak on the outside metal ring area.