Why are you asking for the code? You won't learn by us just writing the code for you. I will give you the wrong things and also I will explain it, hope you will understand...
So. First of all, in line 10, you don't need to write ,,if'', you can just use it as a condition. Also, 'equals to 5' didn't work for me, changed it to 'is 5'
Also line 10: there is no %attacker% in a every second event. You're looping all players, that's good, so put loop-player (because when you're looping stuff (e.g values in a list-variable) you always put loop- before it. E.g loop {something::*}: if loop-value is ....) instead of attacker.
And line 11 I just changed make console execute to execute console command
You can now change the things in your code.
Also... I just don't want you to use this long code when you can do it easier. There you go, learn from this:
(So if all you want is that a player kills 5 zombie then console executes MW move player rpg then use this)
Code:
on death of zombie:
attacker is a player #tests if it was killed by a player
if {kills.%attacker%} is set: #if the variable exists (so the player may already killed some zombies)
add 1 to {kills.%attacker%} #adds one to the kill numbers
{kills.%attacker%} is 5 #This is a condition. You don't need to write if. If it's true (so the variable is 5) it will continue doing the things. If not, then it stops executing the command. This tests if the variable's value is 5 (so if the player killed 5 zombies)
execute console command "mw move %attacker% rpg" #console executes the command
delete {kills.%attacker%} #Delete the variable for some reasons:p
else: #Variable is not set, 0 zombie killed:
set {kills.%attacker%} to 1 #already one, gg...