I dont think its an Performance-Problem. 
Since an Update of VLC i cant play the 1080-Version of Endgame. 
I think (remember: some other People has the Same problem on the same Part of the Video)  theres some Problem on en- or decoding. 
I remember on my older PCs, if i burned a CD and unzipped an Archive-File on Result my burned CD wasnt working.  Only if i burned the CD without doing anything other there was an perfect CD. 
What im trying to tell: isnt that Possible that the Files has been damaged ? 
@ Lukeskywalkie: 
Ancients 1  on 1080 on my PC -> 97.73 MB
Ancients 2  on 1080 on my PC -> 91.24 MB
Ancients 3  on 1080 on my PC -> 11.86 MB  (You are right, it looks very small !) 
Ancients 4  on 1080 on my PC -> 170.13 MB  (Okay, thats a Big one ! ) 
Ancients 5  on 1080 on my PC -> 33.19 MB (A little small size, too) 
Endgame on  1080 on my PC -> 121.09 MB (This is okay, for this Vid, i think)