Phone not powering on, no LED, but connects to PC

Hi there iFixit members !

I own a Galaxy S8 G950F model and I bought it with SIM Card Reader known to malfunction...the issue is that I odered a new SIM READER and I failed replacing it. What I mean by failing is that I haven't managed to remove it from the motherboard, even after I heated up that zone at 200 degrees Celsius. After I realised I need to contact special repair services I reassembled the phone and the volume up button was stuck as it was pressed but it was some motherboard issue, not the button itself. So I dissasembled the phone 3 or 4 times and I still couldn't fix the issue, few minutes after that phone went dead and came up to Samsung logo after 5-6 tries of reflowing the hole motherboard then went dead and stayed dead...

Now I know the motherboard might be dead but fun fact is that if I connect the phone to my laptop via USB, if I keep Power Button pressed phone connects to PC as "Exynos 8895" but no drivers can be installed and phone storage is not showing up...also I want to mention screen has no input and no LED is turning on when charging or connecting to PC....

Not so worring about the phone, any ideeas are welcomed, I own a P30 Pro now and a motherboard for S8 in my country is around 80-100 bucks but it makes me put some questions and maybe I'll find a workaround...

Any ideeas?