We will be able to pay to soldiers off Bandit Camp and they will spawn next to us. They will protect our base and walk around in Cupboard range.

The soldiers at the Bandit Camp and Outpost are game controlled so i doubt if that would be possible

i think yes, but there can be troubles with moving maybe

Nah, you can control their movement by using the navmesh from plugin. They have SetDestination() Method if I remember correctly. You'll need to inherit the MonoBehaviour and use the Update or FixedUpdate calls to check. (Or just use a timer).
Also you can control their targets pretty much similar. 

hi it should be possible, an example of a plugin PEts where you can control the animals, and K1ll ... works on such a plugin but the project was stopped due to waiting for better AI