I might be able to answer that, prepare for a wall of text.
We’ve had a similar case recently, different circumstances, but also an iodé installation where get_unlock_ability was disabled after installation, even though iodé doesn’t set it to 0 on first boot (unlike FPOS, CalyxOS, etc.).
When you flash the Fairphone factory images, the value of get_unlock_ability at the start of the installation process doesn’t matter (the bootloader needs to be unlocked of course), after all the included images have been flashed it’s at 1, as soon as the phone boots into regular Android userland it changes to 0.
I’m not sure the first part happens with iodé, and my theory is that it’s related to iodé not flashing the FRP partition. I remember that we tried flashing that partition separately when people first started bricking their FP4s years ago, but I don’t know anymore.
So if you started your installation with get_unlock_ability already at 0, and my theory is correct, then that’s why you can’t unlock it again.
(The brick itself is caused by rollback protection getting triggered, likely the iodé version you installed had an older security patch level than the system had before, or one of the partitions had an unexpected checksum value)
I’ve written a step-by-step guide to reproduce that problem over on the iodé forum, but I haven’t had the time to actually check it, December is kind of the wrong month to spend a day setting up your main phone again…
Either way, none of this will help you at this point, sorry. As @yvmuell already said, there’s nothing the community can do, only Fairphone has the keys (for good reason).