Data recovery on a Crashed Fusion Drive / Export data in single user mode without write permission on drive

Hello,

I have been trying to recover data for several days from a Crashed Fusion Drive.

When I boot in "recovery mode" or from an external drive, I cannot repair or mount the drive. I did a data recovery in this situation but all the metadata is missing :( (A few bad blocks found during data recovery)
When I boot in "Single user mode", all my files are here. But I can't export the data because "/sbin/mount -uw /" returns an error. And for using an external USB stick I need to write on disk (mkdir /Volumes/...).

Do you have any recommendation in this situation :

How to export data from single user mode without write permission on HDD ? (Easier than using "nano" and copying the data to another computer :)
How to mount or repair the crashed fusion drive ?

Thank you for your reading, have a great day,

Alexandre (Paris)

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