Rock64 bricked

[shawwwn]

Hello, everybody.

My Rock64 bricked after I incorrectly booted a SD card loaded with an unknown OS (I have many boards, lost track of which OS I put in).
Now it just won't boot anymore, just two solid LEDs.

I tried following instructions from these posts with no avail:
https://forum.pine64.org/showthread.php?tid=6508
https://forum.pine64.org/showthread.php?tid=5008
https://forum.pine64.org/showthread.php?tid=8668

To summarize the things I have done so far:

• stretch-minimal-rock64-0.8.3-1141-arm64.img
  
• u-boot-flash-spi-rock64.img
  
• u-boot-erase-spi-rock64.img
  
• And many different OS images ...
  
• Shorted pin 20/21 or 23/25 to disable boot into SPI
  
• Unplug UART TX line prior to boot up
  
• Connect USB OTG to computer but computer do not recognize such hardware even with driver installed
  

None of above works. Any suggestion?
 
Here are my UART outputs: (it won't even get to the SPL stage)

DDR version 1.13 20180428
ID:0x805 Y
In
LPDDR3
786MHz
Bus Width=32 Col=10 Bank=8 Row=15/15 CS=2 Die Bus-Width=32 Size=2048MB
ddrconfig:6
OUT

Is my board gone for good?
Any help is appreciated!