Bestiary help. possible spoilers!

Hi I need some help with completing my bestiary in this game. I know you dont HAVE to but im a perfectionist when it comes to final fantasy games lol

and yes i have completed the game already, now im on second playthru for all the extras.

So far i am just before the entrance to eden hall, where the bloody great adamantortoise is stomping around, and i suddenly realised i dont have a bestiary entry for the targeting beacon, that the Bulwark enemy can drop during your fights with it. The bulwark appears on the skywalk near the begining of chapter 12, and i know you can backtrack and i did, but its not there, every other enemy is but that one.
Have i now completly lost my chance or is there a way to spawn it somehow??

I suppose this is mostly being asked to all the ff perfectionists, like myself who get crazed over these stupid little things lol any help would be appreciated!

thanks

Is this the same targeting beacon thing from chapter 2 or 3 way early in the game? Can you backtrack to that one?

No its a different trageting beacon, there are only two in the game.
Lol and you cant backtrack to any previous chapter areas, except for gran pulse and only through aportal in the final area or in the post game play.

Oh, I'm only on chapter 10.

You can get back to chapter 12 areas, although I am unsure if the Targeting Beacon is in the accessable areas (ie I don't know how far back you can go). I certainly don't expect you can reverse the large jump you take using antigrav.

You can backtrack pretty far back into Chapter 12, but not that far, unfortunately. The Bulwarker and its Targeting Beacon are not accessible once you get too far into Chapter 12.