raemin is it possible that your friend has one of the OMNIBUS F4 V2 boards with the built in SD card logger?
FLIP 32 - F4 - OMNIBUS V2
FLIP 32 - F4 - OMNIBUS V2 PRO
AirBot sells the same FCs, BTW
I got one of each and neither of them boots dRonin. Apparently they are different from the regular OmnibusF4 without the SD. Another observation is that BetaFlight has separate target for the OMNIBUSF4 and the OMNIBUSF4SD -- the above two boards need to use the latter.
FWIW, the non PRO version, FLIP 32 - F4 - OMNIBUS V2 does get into the dRonin bootloader, but only if I flash the Quanton target. The FLIP 32 - F4 - OMNIBUS V2 PRO version does not even get into the bootloader with any of the dRonin F4 targets I've tried.
I've set up a dRonin development environment where I can build the firmware for testing. I figure the SD card connected via SPI is tripping things up for dRonin. I would need a bit of guidance if I attempt to make this work myself. I imagine the best place to start would be to study the diffs between the OMNIBUSF4 and the OMNIBUSF4SD targets in BetaFlight code.