MacBook on macOS Catalina 10.15.7 not returning disk space after deletion So I believe I have a drive requiring FSCK or a version of this for Catalina. This started first of all when I was trying to get rid of purgeable space by creating lots of files using the dd if=blah blah of=/users/user/bigfiles/bigfile1 etc etc. When I deleted these files I didn't get my disk space back. Even now deleting large video files has no effect, in fact any deletion gets only minimal space recovery or none at all.
I have tried all the usual tricks &quot;First Aid&quot; (in recovery mode) and all the disk checks I know how to do, booted into single user mode etc, and run utilities like ONYX, but even though it didn't fix my disk it seemed to find something wrong. Can anyone please shed some light of the results?
Also some people have suggested this is a local Time machine backup issue so I deleted all my local backups and verified there are none there.
As you can see I have some errors when I scan disk Macintosh HD - Data, I get a bunch of
warning: xf: INO_EXT_TYPE_DSTREAM: found unexpected stream associated with non-regular file

and then a load of
warning; FOUND ORPHAN DSTREAM IDOBJECT (id 384942334 (or whatever) refcnt 1)

The volume /dev/rdisk2s1 appears to be ok
As you can then see from the next screen shot 478GB used and 600MB free
Rebooting into multi user mode I looked at the local snapshots.
I had already deleted all my local snapshots and can show there are none left with:
sudo tmutil listlocalsnapshots /
....and get nothing listed...
Next I run Daisydisk and you can see 0.5GB free so I scan the disk and see that:
498GB total used but if you add the items shown you only get approx 260GB so apparently 240GB has been eaten by the system and hidden somewhere.
Any ideas?
Regards
P.S. so I couldn't work out how to insert multiple files (screen shots and a PDF) so here is a link to a Onedrive directory with them in it.
https://silverfoxpc-my.sharepoint.com/:f:/p/royswift/EoMj7wW0uwtJroUuQWXTfMMBYQVlkbmmRhUsJacEvc4nIw?e=bQ5DJF
couldn't fix this so I reformatted the drive and reinstalled and now I am in the middle of a Time Machine recovery.