Shoulder the Burden "blood offering" idea for anti-tunnel
So this would work like something preemptive survivors can do where they make a "blood offering" at a hook (basement hook if you want to be fancy).
They cannot have been previously hooked and they must be uninjured.
They approach a hook, and select the option to perform "Blood offering". <queue whatever animation you can imagine as if they injure themself on the hook> They become injured and gain the broken status until the next time they are hooked. However, this will transfer the next gained hook state to this survivor.
If the survivor who performed the blood offering is hooked while their blood offering is active the blood offering is cancelled. However, this survivor will remain broken for the rest of the trial if this occurs. (This could incentivize killers to stop tunneling whoever it is they're currently on and instead target this survivor.)
Further, survivors who failed a blood offering (by being hooked while their blood offering is active) cannot receive blood offerings from other survivors.
If a blood offering prevents the death of a survivor the survivor who made this blood offering can be moried once the exit gates are powered regardless of their hook status.
Killers will know who has an active blood offering based on a red glow around their portrait on the HUD. Survivors who can be moried will also have a red glow trail around their character once the exit gates are powered.
Just an idea, might be too convoluted.