Delayed Water Leak Under Dash

[jordan1295]

Got into my 2014 Silverado to find about a cup of water pooled on the floor mat with some also on the e-break pedal. Couldn't see a source look up behind the dash. Dried it out in the garage overnight and went back this morning to run a hose over it for about 15 minutes. After about fifteen minutes of consistent water over the windshield, windshield seal, door seals, and shark fin - I didn't see any water behind the dash (looked up and through fuse panel). About two hours later I found the water you see in the photos on imagur. In the much more level garage the water seemed to be leaking more to the right of the e-break just below that blue wiring harness. Still didn't see any water looking up in the dash.

 

https://imgur.com/a/zK21HxT

 

any ideas?