Comment 1 for bug 1878548

_check_host_status_by_crmadmin [1] is the proper safeguard.
Hostmonitor should be treated as pacemaker proxy so should run on pacemaker nodes (not remotes).
I guess this needs documenting and disabling its functionality on non-pacemaker nodes altogether.
There is no benefit to running hostmonitors on remotes, it can only result in more resource waste and less stability.