250Gb lost after dealing with issues around Plex plugin

[Zola]

Hi All,
I wonder if anyone can help identifying the cause and understand why? Can it be restored?
In a nutshell.
Was going to update Plex from GUI. I cancelled process at 50% as many others now I know I should not have. It stopped working so started troubleshooting. Could not restore metadata as I never had a saved one so decided install a new jail&plugin.
It than got all messy and could not get neither of the plugins working so deleted both plugin but was unable to delete the Jail due to the known "could not be deleted... device is busy" message.
Whilst I was playing in the command line trying to work out how to delete the Jail noticed that two of my folders in my media data set disappeared. These were CIFS shared amongst others but have not touched the folders for sure. Looking the HDD history when I removed the latest Plex plugin 250Gb of data got lost exactly same time. Very weird coincident if so and the kids not happy as about 100films of theirs gone...
I would appreciate any suggestion or advice how to approach this.
Thanks

 

[SweetAndLow]

Removing a Plex jail won't delete any of your data in your pool. If you had that data stored in your jail then it will get deleted. To restore the data you can either use your backup or snapshots if you configured them.

 

[Zola]

That is what I thought and no the data was not in the jail but in a separate dataset. ... no Snapshot or backup unfortunately
Also since I managed to delete all Plex related stuff (plugin and jail) and re-installed all cannot get it working.
Website not coming up. Getting fed up with the whole thing.