Erm, sorry I don't follow you.
The host_options have to be created on the host file which is exported by the monitored hosts with the nagios::host  define and collected by Nagios. I reaffirm: on the hosts to be monitored (the ones that export the nagios host configurations collected by the nagios server) we cannot declare the nagios class, otherwise we would find nagios installed on every node.
Have you tried to apply this patch on different nodes? With what Puppet code?