This isn't even a deathrun/map issue though, it's a plugin issue since any map that has a trigger_hurt can sometimes be avoid by placing a sentry or dispenser over them with rtd. Best solution is to just remove build a sentry/dispenser roll from deathrun.
I prefer to fix this per map because sometimes dispenser and sentry can be useful.
I just create a logic_timer and add the output OnTimer Obj_* Kill
This is good because you can make it kill sentries / dispensers whenever you need it to. Example: in deathrun it's pretty good to have sentry / dispenser at fight minigames, but not at minigames like spinner / anything else that has breaking floors or trigger hurts you can avoid.
Plenty of possibilities if you let the map fix the issue. In my opinion it's not worth it to fully remove the perks.
But if you really need an alternative solution, I'd suggest make the sentry / dispenser disappear when the timer runs out instead of keeping it forever. I'm pretty sure Benedevil can do this already, but to make it easier he can also copy paste it from here. But I still stand for per map fixing because of the control it gives.
Code:
"Effects"
{
"spawndispenser"
{
"time" "20"
"settings"
{
"level" "3"
"keep" "0"
}
}
"spawnsentry"
{
"time" "20"
"settings"
{
"level" "2"
"keep" "0"
}
}
}