You did already a lot of good actions.
Can you check log files for errors:
/var/log/vmkwarning.log
/var/log/syslog.log
/var/log/hostd.log
/var/log/vobd.log
Is vCenter used?
Probably not because it is just one host, but just making sure.
If vCenter is used, restart vCenter server and also connect to the ESX host directly.