So this question has simple answer but maybe some explanation is needed.
What you are describing (I believe) is that you, or your faction, wishes to hire a PA leader. This PA leader will help carry 3 of your existing faction members to complete a PA successfully.
Ive heard it being done before but I am led to believe this sort of arrangement is very rare.
2 main reasons why:
1) The person to be hired as the PA leader will lose out on their home faction's upgrades and community (such as maybe their home faction does giveaways and contests or such)
2) The faction hiring them loses out by hiring them. PA's are not guaranteed. PA leads can bill the faction on attempt and/or a majority portion of the PA success money.
Your faction needs a goal as to why you want to do a PA and decide if it is worth hiring a PA leader.
Need respect from PA? Do more chains.
Need money from PA? Take territories and cause drama.
Just want PA's to grow the CE of lower members? Yeah I can see this, but Torn is a marathon not a sprint, plane hijackings are pretty good too.