This would be available to all survivors as another action (not a skill).
Takes one action, but ends survivors turn.
For one action a survivor can pin a walker or runner in the same zone as she/he.
A pinned zombie does not count toward the extra movement cost to leave zone for other survivors while pinned.
Roll a die, on a roll of 2-6 other survivors gets a +1 to die to attack zombie, on a 1 the other survivors gets a -1 to attack and the survivor has to be rescued by another (pinned by zombie).
The next turn a pinning survivor can cease to pin and move away without the regular cost of extra action points (imagine a shove), this does not affect other zombies in area.
If other zombies walk into zone with a pinned zombie, the pinning is considered ended.
On zombies turn roll a dice, on 4-6 the survivor takes a wound. This is to avoid this being used as a go to tactic every time a survivor is down to a single action, may instead consider making it take 2 actions - will play test more.
This give you more options early on for players with poor equipment like pans or pistols (with others in same area) - such equipped player can pin to give others higher chance to hit or to get past a single zombie.
This is also to allow getting past zombie(s) without having to kill them if your play style is to avoid.
I think it is quite thematic as the pin zombie move against the wall etc is quite common to allow others in group to run past.
Interesting idea, very thematic.