I've taken care of most of the finding:
Share flash is identically named to a disk share AND
Reserved user share flash
Confirmed my flash drive was not set to Export
Confirmed directory was empty
Renamed directory, rebooted, no issues and confirmed error no longer reported in FCP
Macvlan and Bridging found
followed https://docs.unraid.net/unraid-os/release-notes/6.12.4/#fix-for-macvlan-call-traces
changed "Docker custom network type" from macvlan to ipvlan
confirmed error no longer reported in FCP
Share Docker /set to not use the cache, but files / folders exist on the cache drive
enabled cache drive use for Docker share
Jumbo Frames detected on eth1
changed MTU to 1500
disabled eth1 since I'll be taking this card out soon
Marvel Hard Drive Controller Installed
I'm going to leave this for now. I haven't experienced random drive droppings offline.
Unassigned Device Plus not installed
I do have an unassigned device but it's not being used. Marking IGNORE.
Transmission Permissions
I followed your recommendation and added the variables, it seems to be working now.
pihole
left this for last. I completed the password reset once more, confirmed I could log in, restarted the docker instance and the credentials didn't work again.
Version info
# pihole -v
Pi-hole version is v5.18.3 (Latest: v5.18.4)
web version is v5.21 (Latest: v5.21)
FTL version is v5.25.2 (Latest: v5.25.2)
Could this be related to the my Share Settings?