Water leak on floorboard...not the AC tube or sunroof drain!

Hey folks...interesting situation here. 2011 Prius IV with sunroof and solar. I have a leak that is coming from somewhere up under the dash on the drivers side. During rain events, I get a ton of water on the drivers floorboard. I have pulled out the carpet kit, seats, center console, etc. I can tell that the water is coming from up behind the dash on the drivers side but cannot see specifically where it enters due to all of the wiring harnesses, steering mechanics, etc.
I can confirm that I have thoroughly checked the AC drain tube and it is clean. I have also checked the sunroof for leaks and cannot detect any. This form of sunroof does not have drains that I can see...only channels that direct water to the top corners of the windshield. I have had the windshield pressure tested for leaks...all good there too. I have pulled the fender well liners and cleaned out the water drain areas of debris. I have pulled the cowling at the base of the windshield and cleaned everything there, too. In short, I am at a loss.
I had the car dried out last week. It rained for 3 straight days. I went back inside to find a huge puddle on the drivers floorboard and the firewall insulation all wet. Most the of the wetness was on the left side (viewed from sitting inside). So I'm looking for help. Thank you in advance! Any suggestions???