In a raid you lose the group xp bonus, and on top of that there is a exp penalty, and on top of that you are spreading whats left of any exp accross 10 characters. The RAF bonus should still work, however it will only triple the already gimped exp.

Your first RAF method would get you Zhevras on all 5 of your original accounts, but it would require every account to be logged in to receive bonus on all characters. You couldn't sit one out in that case. I would set up the referrals so you can do 2 groups independantly, if you want to 10box. If you just want to 5box, you can just get 3 RAF accounts, link 2 to one account, and the third to another, and xfer the toons on your other 3 accounts to the new ones. More costly, but less time consuming. What do you have more of? Time or money