Forward Log shows "not allowed"

Not allowed by implicit   deny is typically not  logged. 1st you need to enable log on the  policies of interest regardless if it's allow deny

config firewall policy 

    edit 777

         set log-forward-traffic enable

end

Next for logging implict deny, you need to enable that.

config log setting 

    set fwpolicy-implicit-log en

end

keep in mind if your logging to memory,syslog, disk,etc.... your just threw more load and wasted diskspace/memory-usages and the logs will roll more often

Ken