If you cannot fix the issue. one solution is to re-install ESXi onto the host.
Obviously, install ESXi to new media / or a new USB drive to keep all existing storage intact
(Assuming you are using local disks for the datastore that the VM is on.
However, if the datastore is on an external device such as SAN or NAS you can try to mount the datastore / lun etc onto another host if you have one and access the VM from there by browsing the datastore and adding it back into the inventory of a new host)