Rule of thumb: Never patrol with more men than you can control.
Say 7 of yours, and 3 allies. 12 of yours and 10 allies.
Be sure you can wipe out all the “allies” at any time. Then, they are likely to be loyal. Some of the patrols will come back with all the loyal allies as casualties, left on the field of battle.
Give your allies every incentive to police their own. They will have to do it after we leave, they can practice it now.
Unfortunately, I believe your ‘rule of thumb’ is contrary to our PC ROE. I hope to hell he spends some time in schools, until we pull out of that $hithole.