Nothing you have done is the correct way to get the disk enabled. In fact, it was all a waste of time and effort and possibly even dangerous since your array was unprotected while you did all that, and it also had potential for further user errors.
Disk looks OK. Syslog doesn't have anything from before reboot, so nothing to indicate what caused the problem, possibly a bad connection.
Stop the read check, it is also a waste of time.
To rebuild to the same disk
Stop array
Unassign the disabled disk
Start array with the disabled disk unassigned
Stop array
Reassign the disabled disk
Start array to begin rebuilding the disabled disk.
If you had asked before doing anything this is what we would have told you to begin with.
And even though you formatted the disk, it still has to be rebuilt. All that stuff you think you did with the disk, including the format, was really just to the emulated disk, not the physical disk. The physical disk hasn't been accessed by Unraid since the moment it was disabled.