Good brand but requires reflow temps upward of 230C(unleaded), instead opt for leaded 63/37 (approx 180C) and try getting it in a tub so it’s easier to mix, apply, store and add flux when it inevitably dries out.
Does backlight turn on or blink at black screen?
SoC getting warm indidcates it’s prompted to boot (even in a “braindead” state) so this is normal behaviour. If the SoC isn’t getting warm after plugging in USB (instead of hitting the power button) it indicates the USB isn’t prompting the console to boot and there is an issue with either the USB or related support circuitry. In this case I’d search the forum for “ESD diodes” and test they are good, check your fuse, check you have no bridges between pins on the USB and filters (above P13) in continuity on your meter, idealy you’d check the USBC with a breakout board.
I don’t think it’s the root cause of your faults but it’s possible it’s preventing you from having a display. Scorched plastic turns to carbon, carbon == resistor, carbon going directly across the active latch pins (at the very least) places a “resistor” across all conductors this likely isn’t a huge problem in your case but it’s something to watch out for as it can cause more serious problems later down the road in more sever instances
Also the swelling could also have a negative impact which prevents the conductors from making contact, these connectors have incredibly tight tolerances, to the point where I’ve had situations where a different manufacturers LCD’s on another switch won’t work because the alternative manufacturers ribbon was a fraction thicker, thus “stretching” out the connector/conductors preventing the replacement LCD working.
btw you’ll likely want to go over those pads with wick one more time and flatten them out a tad more prior to reballing and fitting the WIFI IC