if ($nick !isop $chan) && ($nick != isvo $chan) { Besides the small typo, the most clear sollution to exclude ALL ops and voices (what about %halfops, &protecteds etc (if the ircd allows these modes)) would be imho: make the script evaluate the other way around: make it trigger only for regular users (that is: users without ANY mode prefix/channel privilegues)
stop processing for non-regular users:
if ($nick !isreg $chan) { return }
or proceed if it's a regular user:
if ($nick isreg $chan) { protection stuff }
