All Shares except flash disappeared after drive replacement, the seem to be intact via the gui. No errors to speak of. At a loss of where to go from here. Haven't found any solutions that worked for me in the forums. Any ideas?

sihome-diagnostics-20210723-1328.zip

According to the syslog you have file system corruption on disk2.    You would need to run a file system repair to fix that.

 

you mentioned a drive replacement - which one and what was the trigger for deciding to do that?

Disk 2. the one currently in place is the replacement drive. 
How do I run the repair?

I believe I figured it out. Thanks for your help!

There is comprehensive documentation accessible via the ‘manual’ link at the bottom of the Untaid GUI.    All the information you need should be in the Storage Management section.