Problem solved. Went to poke the damn flash and first thing that was missing, was its power... Well then. Found its schematic and dismantled the whole machine. Obiviously some coffee-accident, couple of placed on pcb looked quite bad. Traced these interesting parts and found one unfortunate exposed copper-pad, which had lost its connection to its trace. Soldered some metal in its place and flash suddenly has its power back. And wattmeter shows 20w and other bigger numbers at times.

And thats not all, success did not stop with usb-c charging improvements. I had some dell-branded usb-c...

Ho ho ho, badcaps people,

if this qualifies as bios request, hopefully. Actually BIOS2 for that laptop is second smaller SPI flash (Winbond W25Q80DVSNIG-GP-U), containing supposedly some config for TPS65988 which in turn manages USB-C stuff, including PD. This is possibly flash, where update "Power Delivery Firmware (TI TPS65988)" F407.06.29 -- [URL]https://download.lenovo.com/pccbbs/mobiles/r10pd10w.exe[/URL] does its thing. Previous owner claims that after clean install of Windows 10 he installed thinkvantage tool of sort, which updated everything for that laptop. I did...