this is the best I can do for what you want.
open up the file "TF341_Main_Default.fpi" in notepad
locate the section that looks like this:
;//Team Behavior
;//Look around occasionally
:varequal=cooldown 2000,random=50:rotateheadrandom=50
;//Auto follow if player stays relatively close
:state=1,aiteam=1,plrdistwithin=200,plrdistfurther=100,aihastarget=0,aicanshoot=0:aifollowplr=1,state=2
:state=1,aiteam=1,plrdistfurther=500:aifollowplr=0,state=2
:aiteam=1,plrdistwithin=100:aifollowplr=0
;//2ndary Characters can move around occasionally
:aiteam=4,varequal=cooldown 1000,idle=1,random=500:aimoverandom
:aiteam=5,varequal=cooldown 1000,idle=1,random=500:aimoverandom
then change this line:
:state=1,aiteam=1,plrdistwithin=200,plrdistfurther=100,aihastarget=0,aicanshoot=0:aifollowplr=1,state=2
to this:
:state=1,aiteam=1,plrdistwithin=2000,plrdistfurther=100,aihastarget=0,aicanshoot=0:aifollowplr=1,state=2
the plrdistwithin= sets the distance he is called
there is a cooldown variable so after he kills the enemy he will secure him then when timer is up he will follow player.
you can increase the number more but 2000 works for me.