I'm not %100 sure, this will work.
You need run weapon restrcit plugin beside.
[CSS/CS:GO] Weapon Restrict
("Weapon Restrict" (4.0.0-b7) by Dr!fter)
I wanted to keep "sm_restrict_immunity_level
" as it is, so you need change this admin access to "z" flag.
And I recommend to not give root access "z" to any admin, this way SourceMod admin system work nicely. It's up to you.
This plugin use another admin access called "sm_vip"
, by default it will work admins with flag "a".
You can change "sm_vip" flag from admin_overrides.cfg as well.