Hinterlands Mosaics "The Fall"

OK guys, i think i found an answer (kind of) to this problem - there is no answer. 

Following this guide:

https://www.facebook.com/pipedream420/media_set?set=a.905296806189230.1073741825.100001267579195&type=3

my friend managed to get here:

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpa1/v/t35.0-12/10951034_1067506459941828_1026882214_o.jpg?oh=b830d212acf4db6fcbc0fd585ce13b92&oe=54CB5C09&__gda__=1422533656_4915ceff9e23634ab8c64b69c71df1f9

(excuse the crappy quality, he took the pictures with his phone) which, on the map, is here 

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t35.0-12/10952481_1067506463275161_1481338281_o.jpg?oh=f63e91e6633650cee19f540d1d0d5037&oe=54CB6BBD&__gda__=1422556873_c3d2ec61aa14f8ef764b48f8be1c0940

Notice that this is directly behind the rock wherein the 12th mosaic piece supposedly lies. Through mounting and dismounting, he actually managed to get INSIDE this rock, and we expected to easily pick up the last piece, as shown here:

http://i.imgur.com/KsxVjCW.png

Here's 3 pictures of him inside the rock 

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t35.0-12/10944684_1067506449941829_1101207692_o.jpg?oh=136178c535394dc542a1f0fda19cca6c&oe=54CA9448&__gda__=1422614012_321c28d5839a790b782b0ef17aad6f58 

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t35.0-12/10955810_1067506453275162_1886405701_o.jpg?oh=8f22ae19688cc81cfcc1219ff457b547&oe=54CA8EAA&__gda__=1422553182_7fe2b0fc444dc811e01e7e7ec2633adf

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t35.0-12/10954258_1067506456608495_1744757658_o.jpg?oh=185ccaf28511a20b0f4fa4c24907eb41&oe=54CA7716&__gda__=1422614434_88315f831f1f00f7bd927248802228c9

Now, upon entering the inside of the rock, his character got either stuck, or glitched out and fell down, flew into the air, and other such things which characters ought not to be doing. However, if none of this happened (he had to reload a few times) he would be able to stand still and click the search key, yet nothing would pop up - that's right, there was neither a ping nor a highlight of the mosaic piece. When going with the cursor over its supposed location, we couldnt see it, click on it, or make out anything whatsoever to stand out from the dark background.

Our guess is that even if the moasic piece is there, it exists as a static environmental prop, not something you can interact with. So if it is any consolation, no matter what you do, even if you enter the very bugged rock itself, you CANNOT pick up the mosaic piece.