@MyBios8MyHamster
As an Intel platform, there may be a chance with Intel FPT tool from ME FW 14 tools package (14.0 or 14.1 ONLY) from C. Intel (CS)ME System Tools on the linked thread…this besides EFIflash…
This this requires a little knowledge of it and requires that SPI access to regions be unlocked for read/write, at least to bios_region.
Still…the results can be unpredictive, but at least this board USB Q-Flash that may provide a bios recovery, again unpredictable.
Last resource is using an SPI programmer like CH341A or similar.
You should wait for other users, before any action with this tool.
Carefull, this tool (FPT) will write ANY DATA to the SPI without any warnings of bad user actions or wrong data provided to it.
Good luck.