Question about Titan Runestones -help please

So I ran ToT 3 and 4 and got my 20th secret off of Shen.

Did Thunderforge and the Nalak thing

Now I have the quest to gather the runestones

Can I go back to all the ToT 3 and 4 bosses that I killed and rekill them with a chance for a runestone?

Thanks.

You have a chance to obtain either a Secrets of the Empire or Titan Runestone from each boss once a week. That means you won't be eligible for the runestones by reattempting Throne of Thunder wings 3 and 4.

However, you should still be eligible for a chance to have the runestone drop (with Sha of Pride being a guaranteed drop) if you haven't yet completed Siege of Orgrimmar wings 1 and 2.

If you still have questions feel free to look over this post for the Legendary quest line. http://us.battle.net/wow/en/forum/topic/10137754011#2