Adding a Random Seed and/or 'Refresh' toggle to a Random Mesh on Spline Blueprint

Hi, I have created a handy tool for creating a crowd in my scenes, based on tutorials and help from others… but I need some help please…

You adjust a spline and the BP populates it with random meshes - with the Rows control then adding more random meshes behind for x-number of rows.

This example shows the girl in the pink shirt too close to each other. The only option I have is to keep dragging the BP into the scene until I get a random layout I like.

What I would like to be able to do is have control of the random element…

Either:

Use a random seed that allows me to enter a number that will let me adjust the randomised results until I’m happy.

OR

A ‘Refresh’ or ‘Reset’ toggle that will re-randomise until I’m happy.

I can’t see any way of adding either of these to the current blueprint - can anybody help?

Thanks!