Suggestions requested: water leaking/ draining into cabin & trunk
 

New for forum, seeking help.

2016 Civic EX with low mileage.
I found this with a large amount of water in the trunk, heard the sloshing when backing up. Felt rear passenger floor was wet too.
Wet Vac'd, fanned, until dealer could look at it. I presumed it might be sunroof drain (not realizing maybe too young of a car for this) as a neighbor had this problem.
Dealer said it was due to tree debris clogging up gasket, didn't offer to show me, cleaned it and treated it superficially with a bunch of silicone.
So I can't prove now if the gasket was installed correctly.

I have an after-market windshield (original cracked due to chip) and am taking this to a third party to inspect for leak here or on the body somewhere else.
I learned about the AC evaporator drain and am wondering also if there's any unknown body leaks. I ran a lot of water over the tail-light areas and couldn't find a leak myself.

The car is mildew smelling and not getting any better. I've got damprid in the car and a de-humidifier at night.
If we don't find any leaks that are warrantyable, I'm faced with 2 options:


1. Have a dealer replace the whole carpet on the interior, removing center console and dash so they can get under it. Detail while it's open. Ozone. $1950 estimate.
2. Have an detailer take out the seats, clean/detail it up, strip out the padding, and put in after market padding. No dash removal. $775

Both I would advocate for digestive enzyme treatment, heat, etc, to kill off any brewing mold.

I feel like my best move is to trade in the car.
I'll have it appraised for trade in without any work as-is and hear just how low ball that goes.

Am I better off doing #1 or #2 if I want to just trade it in?
I'm wondering if #2 is best given the price difference.
I feel like a dealer will want to know it's cleaned up and doesn't smell after, less so caring if it's original stuff or the padding has been replaced.

Your advice is humbly appreciated! I'm not much of a car guy and am learning on the fly.

Best case is that there is indeed a large body leak or windshield leak and I can seek full remedy, maybe even total loss.