Reassignment of Task

I am facing some problem in reassignment of task in Appian 7.10.

Consider the scenario where a task is assigned to Group Z

For that task, particular user input task node for a process model, we had set re-assignment privileges for assignees for Group Z set to "Can reassign the task within a pool of assignees".

User Z of Group Z are able to perform the following

a) Choose from all assignees
b) choose from all users and groups

However choose from all assignees is fine but as per business requirement we should not be able to reassign to all user and group.

Ideally only choose from all assignees should be visible

Is there any possibility to hide choose from all users and groups from the reassign task?

OriginalPostID-233620