Can't boot into recovery mode - I get a black screen

Hi all,

Long story (maybe someone can point me in the right direction as I'm a macOs noob.

I have an old 3TB external disk that I used for a few things (backups mostly), and for some reason one of the partitions is on HFS Plus (it says:Mac OS Expanded (with journaling) ) and the other one I don't remember (maybe APFS?).

My iMac had macOS High Sierra and I used OpenCore legacy patcher to upgrade my 2011 iMac to Monterey, all went fine but in the meantime I noticed that missing partition...

My HFS Plus partition is all good and checked but the disk, if I show all devices and do first aid it fails, error fixing partition map, not possible change mapping -69874, and from what I read they all metion bootint into recovery.

Reading this: https://forums.macrumors.com/threads/partition-disk-disappeared.2234920/, I start to think that missing partition is on: HFS+, with some suggestions to go to Recovery or Internet Recovery and try to fix it.

Problem is, when I select recovery boot in OpenCore Legacy Patcher, I get a black screen and I can't do anything...

All others seem to work fine, openshell etc.. (I still boot from USB not sure if that's the reason)

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